


Discoveries

by Aithe



Category: Undertale (Video Game)
Genre: Adopted Sibling Incest, Aged-Up Character(s), Alternate Universe - Asriel Dreemurr Lives, Anal Sex, Asriel is 17, DMAB!Frisk, Emotional Confusion, Eventual Monster!Frisk, First Love, First Time, Frisk is 16, Hand Jobs, M/M, Mentions of past abuse, My First AO3 Post, Not sure if that counts as underage so tagging to be safe, Oral Sex, Phone Sex, Possessive Asriel, Rimming, agender!Frisk
Language: English
Status: In-Progress
Published: 2016-01-12
Updated: 2016-10-06
Packaged: 2018-05-13 08:00:51
Rating: Explicit
Warnings: Underage
Chapters: 16
Words: 81,335
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5701018
Author URL: https://archiveofourown.org/users/Aithe/pseuds/Aithe
Summary: <blockquote class="userstuff">
              <p>Years have passed since Frisk broke through the barrier and brought monsterkind to the surface. Now living a peaceful life with their elder brother and parents, everything seems to be going fine.</p>
<p>Until they're tired and allow Asriel to do things to them, that is.</p>
            </blockquote>





	1. Chapter 1

**Author's Note:**

> Hey, Aithe here. I haven't completed a fanfiction before, and even this is only a oneshot of sorts. If it gets recieved well enough I might continue it, providing I can figure out how to. Either way, forgive my bad writing style as I'm still trying to get back into the swing of writing. Any constructive criticism is welcomed!

Sleeping together had never been an issue before. There had only been one bed per bedroom in Toriel’s home on the surface, but with how small Frisk and Asriel had been back then, the size of the bed was more than enough for the pair of them, with extra space to boot.

But that was a long time ago now, years even. While Frisk wasn’t overly large for a human, Asriel had taken after his parents when it came to sheer size, easily dwarfing his younger sibling. It made sleeping together rather more difficult, and the new sizes of the pair was only the beginning of the problem. With the amount of time that had passed, both of them were struggling with all the additional complications of puberty.

With all of those issues, it wasn’t exactly a surprise that things would become rather more awkward between the young teens.

“Frisk, do you really need to do this right now?” Asriel spoke quietly, the sun having set long ago and not wanting to awaken his parents.

“It’s too hot in here, I can’t sleep in pajamas. If it bothers you so much, go sleep on the couch.” Frisk’s reply was as quiet as his brother’s, although somewhat snarkier. Hormones were much more influential for the human, leaving him cranky when he was tired, as he was now.

“You don’t have fur, don’t complain that it’s hot.” Asriel replied, shifting so that his head was rested in the crook of his elbow, wearing his loose pajamas an silently wishing that, at times like this, he and Frisk didn’t share a bed so that he’d be able to sleep without covers or clothing, with a much lower risk of a lethal dose of shame and embarrassment for doing so.

Frisk decided that he wouldn’t get any more sense out of his tired head at this point, so as he finished stripping down to underwear, he climbed into the large bed alongside his adopted sibling, rolling so his back was against Asriel’s chest, causing the young goat monster to shift a little so that the position wasn’t too uncomfortable.

“Y’know, complaining that it’s hot and then getting into bed with me seems hypocritical, Frisk.” Asriel spoke quietly, his large, muscular furred arm falling over the smaller sibling’s midriff and pulling them closer, a light embrace being shared between the two.

“Comfort comes first. And you are very comfortable. Now stop talking so I can sleep.” Frisk replied shortly, a long and somewhat overdramatic yawn escaping their mouth moments after they finish their reply.

Asriel simply nods, holding Frisk tight against them and trying to also get to rest, although he found the summer heat was rather stifling, especially when combined with having to wear clothing to bed as well as the body heat being shared between the two of them. With sleeping currently out of his reach, as much as he wishes otherwise, Asriel simply lets his eyes close and his mind wander.

Whenever he got the chance to, Asriel enjoyed quiet relaxation like this. It allowed him to think in detail about all the things that had happened over the past few years, since the Barrier had been broken. Toriel had struggled to come to terms with Asriel’s rebirth, as was to be expected. But, no matter the circumstances, Toriel’s maternal instincts were not to be denied, and so it had become that Frisk and Asriel were now siblings, of a kind.

That being said, Asriel had always found Frisk very confusing, even after he had come to the surface and seen other humans, Frisk had always stood out. Perhaps it was because Frisk was only the second human he had ever met. Perhaps it was how Frisk was so kind and always showed MERCY. Asriel tried not to think too hard about it, in truth. Frisk was just Frisk. Beyond that he didn’t really care that much.

Well, no, that wasn’t strictly true. Asriel cared intensely about Frisk. The pair had become friends quickly since the Barrier was broken. The bond between them only got tighter with them becoming adopted brothers, which Asriel saw as both a blessing and a curse. While Frisk was a wonderful sibling, there were some parts of their personality that Asriel found thoroughly embarrassing.

 

Chief of which, to the surprise of nobody that knew the pair, was Frisk’s incessantly flirtatious nature. If Asriel didn’t know better, he would assume that his younger sibling was doing it purely to embarrass him. Asriel hoped he knew better, at least. Knowing Frisk, it wasn’t exactly impossible that was the situation, but Asriel hoped it wasn’t. He’d have to ask about it in the morning.

For now, however, Asriel found himself feeling too tired to continue with his thoughts, so he held Frisk tighter against him as he fell asleep.

\----------------------------------------------------------

The first thing Frisk noticed when he woke up is that he was much closer to Asriel than he remembered being when he got into the bed. They normally tried to get as much space for each other as they could, but the human found themselves nestled right up against Asriel, with their back up against their elder brother’s stomach. Before he’d realised it, Frisk’s normally neutral expression turned into one of rather intense embarrassment. Physical affection wasn’t alien to them, far from it. But waking up, effectively wrapped in a blanket of warm, soft, muscular goat...it was difficult for even them to deal with. It took all of the willpower their tired brain would give them to stop them from curling up closer to Asriel an simply falling back asleep. Not that they had any plans on leaving their currently very, very comfortable position, but they needed to stay awake. 

So, too encompassed in pure, white-furred comfort, Frisk simply lay there, allowing their mind to wander. This was a decision they rather rapidly came to regret when Asriel’s shifting meant that the large goat-monster was literally breathing down their neck, causing intense shivers down Frisk’s spine. Closeness like this was very comfortable for Frisk, but the human very suddenly came to realise that their position was, while not particularly compromising if either Sans or Toriel were to walk in, the lack of clothing on Frisk may make things rather awkward.

And that wasn’t even mentioning the fact that, with how close the two were, and Asriel’s warm breath hitting the back of their neck so routinely, Frisk found themselves very uncomfortably aroused. He hoped, silently, that Asriel would stay asleep until the tensing in his muscles and burning beneath his belt went away, as it normally would if he paid no attention to it.

“Good morning Frisk.” Asriel’s voice was quiet, and tired, and given Frisk’s current problem, incredibly worrying. They struggled not to sound too flustered when they replied.

“M-morning. Sleep well?” Frisk also replied quietly, not entirely sure what time it was, due to the summer sun having already risen. They didn’t want to wake their parents up, after all. Frisk was focusing very, very hard on keeping their breathing regular and paying very close attention to where Asriel’s hand was. Doing that made it significantly easier to not focus on the embarrassment of their aching arousal, and that was all that mattered to them right now.

“Mhm.” Asriel’s reply was short as he nuzzled against Frisk’s shoulders, smiling as they hold their smaller sibling close against their chest. “Why are you so tense? Didnt you sleep well?” Asriel’s tone was soft, and almost as motherly as Toriel’s, which only made the rather shameful aching beneath Frisk’s underwear worse.

“I slept fine. Don’t worry so much.” Frisk cursed themselves silently when even they heard the crack in their voice, giving away that they weren’t being entirely truthful. Now even more embarrassed than they already were, the younger sibling simply bowed their head and hoped Asriel wouldn’t call them out on it.

Of course Frisk couldn’t be that lucky. He heard a quiet laugh that, much like the warm breath flowing down his back, gave him shivers and very nearly caused him to whimper. In that moment, Frisk was very glad of the amount of willpower he had, although he was significantly less glad that he was using almost all of it to not be reduced to a blushing, embarrassed mess.

“What’s the matter? Did little Frisky have a bad dream?” Asriel laughed, his arm moving down from Frisk’s chest to his midriff, where he noticed a slight, but noticeable change in temperature. It made him wonder what exactly was going on, but he didn’t want to embarrass Frisk more than they already obviously were. Frisk’s embarrassment was only made more apparent when they grabbed Asriel’s hand, pulling it up away from their waist with no real warning.

“Keep your hands up here, okay?” Frisk said, tensing up against Asriel’s stomach. Asriel’s hand had gotten dangerously close to their waistband, so Frisk was forced to take action against it. They hated touching anyone without explicit permission, but minor inconvenience was less of an issue than Asriel accidently becoming aware of Frisk’s arousal, which was just as torturous now as it was when it began.

“Oh, I get it. It wasn’t a nightmare, but something more...’Frisky’, huh Frisk?” Asriel said, chuckling quietly as his grip tightened a little around his younger sibling’s body, holding them very closely. That explained the heat Frisk had lower down their body, at least. And if the rather frustrated groan that ame from Frisk is any indication, the pun-laden question wasn’t very far from the truth.

“Don’t be a jerk, Asri. Everyone gets like this sometimes.” Frisk’s reply was somewhat clipped, worried that something like this, as natural as it was, would make the situation more awkward. Not that it wasn’t awkward already, but it could always get worse. And, despite keeping his hands firmly over Asriel’s hand, the warmth his caprine brother was giving off, as well as the intimate closeness of the pair, meant that Frisk’s arousal was both intense and very determined to not go away.

It only got worse, and quite significantly so, when Asriel pulled him closer and he felt Asriel’s crotch, thankfully clothed, being pressed up against his lower back. Frisk was rapidly finding it harder and harder to keep his mind clear of any overly dirty thoughts about his very large, muscular brother and the kind of things that he could do to Frisk on the bed they were currently laying on.

It wasn’t working very well, and Frisk found themselves curling up out of shame. They hadn’t even tried all that hard to keep their mind away from Asriel. Frisk didn’t want to think about it that much. They felt dirty, and ashamed. Sure, they knew they were a hell of a flirt, but it was never serious. And Asriel was their brother, of all things.

“You don’t have to curl up like that, Frisk. It’s not like you have to be-” Asriel’s attempt at trying to calm Frisk down were cut short when the human, in a rare fit of emotion, interrupted him.

“I’m very embarrassed, Asriel. Don’t tell me not to be. You’re the one who made me like this, so shush.” The interruption wasn’t very long, but Frisk felt their stomach roll when it was over. That was an admission, nothing less. They’d been trying as hard as they could to push the reason away and not admit it, but look what had happened now.

Now Asriel would think they were a freak, or worse would become permanently bothered by this. Something so stupid as a tired reaction to intimate contact may have done a lot of harm and now it had happened and Frisk felt like a huge idiot.

“Wh-what do you mean, I did this to you? Did I touch you while I was sleeping or something?” Asriel questions, now intensely flustered and somewhat bothered that Frisk hadn’t at least tried to roll over to face him, although it wasn’t exactly unreasonable that they hadn’t.

Nor was it a surprise to the caprine when Frisk’s only reply was a very embarrassed, awkward silence. Asriel didn’t really know how to process the idea that Frisk’s arousal was caused by him. It wasn’t that he wasn’t aware that a lot of monsters, and humans for that matter, found him attractive. But Frisk? And enough that it had made him like this?

“Do...do you want me to apologise, or something, Frisk?” Asriel asked, now perhaps more nervous than Frisk was, although of that he couldn’t be sure. Somewhat more explicit ideas ran through his head, but he remembered that monster culture was different to human and such things were heavily frowned upon for their kind.

“No, you idiot. I just...I want it to go away. I’m so ashamed. I-I can’t believe my own brother got me hard like this.” Frisk’s voice was quiet and cracked while they spoke, the grip they had on Asriel’s hand was gone. They just let it drop as they hugged themselves tightly.

“You make it sound like it’s a big deal. Lots of people get aroused when they wake up, dummy. Don’t worry so much.” Asriel replied calmly, holding Frisk tightly against them and making sure to keep his hand safely above Frisk’s waist, to keep them from panicking. “I could help if you want.”

It was a statement given casually, but it caused Frisk to completely freeze and tighten their grip on themselves. It wasn’t panic that went through their head, but confusion. Asriel had so suddenly an calmly come out with something so completely fitting of the situation yet also completely messed up to Frisk, in a lot of ways. After all, they were siblings. Not...by blood, but paperwork said that they were so that had to count for something.

“Help me? I ho-hope you aren’t implying what I think you are, Asriel.” Frisk replied, quieter now, not out of embarrassment but out of fear. If their assumptions were right, Asriel had basically just said that he’d be willing to have sex with him. And had said so incredibly casually, considering that Frisk assumed Asriel was, like himself, still completely without experience.

“That depends on what you’re thinking.” Asriel says, leaning into Frisk and nuzzling against them, moving their hand out from beneath Frisk’s and pushing it back down toward the smaller sibling’s waist, although Asriel didn’t want to worry Frisk too much so he chose to simply leave it there. “If it’s really such a problem for you to be aroused, I can help.”

It took everything Frisk had not to panic. His voice abandoned him and he cursed internally when he felt annoyed that Asriel had kept his hand up as far as he did. Deep down, Frisk knew this situation was bad. Having his adopted brother literally offer to help him get off was not at all okay. But thinking clearly with the dull ache of arousal pulsing through you isn’t a task that you can keep up forever, and Frisk was starting to think that maybe it wouldn’t be so bad if it was only once. Just to fully realise how stupid of an idea it would be.

Of course, if either Toriel or Sans found out, he may just die on the spot out of embarrassment and shame, but that was going to happen regardless. So, with a variety of complex emotions running through their head, Frisk softly nodded, giving in to Asriel’s offer. But only this once.

Asriel held Frisk close against him, concerned at just how conflicted Frisk seemed about an offer he didn’t quite understand the potential ramifications of. He didn’t want to make any movement too suddenly, for fear of scaring Frisk, but Asriel also found himself nervous due to noting just how significant the size difference between the two of them was. Thankfully, Asriel himself wasn’t aroused, but he now knew that he hadn’t actually thought about what he would do to help Frisk out.

“Are you sure, Frisk?” Asriel asked softly, as much for his own sake as their sibling’s. Frisk’s reply, another short nod, didn’t feel overly satsifying as an answer, but Asriel assumed it was simply because Frisk was embarrassed. He himself was embarrassed after all, and things like this weren’t very unusual in his culture.

“Alright. But tell me if I do anything I shouldn’t do.” Asriel said to Frisk quietly, before moving his hand down further down, over Frisk’s tented underwear. He found himself a little surprised that Frisk had been aroused for however long their conversation had gone on for. Not that he minded, of course. If he was able to help Frisk out, that was all that was important. 

So, with a set goal in mind and being curious as to just how Frisk would react to his touch, Asriel pushed his hand behind the waistband of Frisk’s underwear, holding the fabric away as his large, furred hand wrapped around Frisk’s aching arousal. It was warmer to the touch than Asriel expected, and Frisk seemed very sensitive to being touched there, as he felt his younger sibling’s back arch a little against him.

That, at least, seemed to imply that Asriel was doing the right thing. So, continuing seemed like the only course of action he had. Leaning into Frisk a little, to reassure him that this was okay, Asriel slowly started stroking Frisk.

A quiet, choked whimper escaped from Frisk, even though they’d tried to keep it in. Frisk had his eyes firmly closed, almost overwhelmed by how the situation had turned out. Asriel felt so soft against him, and he just couldn’t find it in himself to resist any longer. There would have to be some serious conversations when he was done, but Frisk resigned that for now he would be fine just enjoying how this felt, while trying to vehemently ignore the fact that it was his brother who was the first person he’d ever shared intimate contact with.

Not that that was hard. Focusing was near-impossible right now. The feeling of Asriel’s hand on him, when they were already so aroused and pent up from not having the time to relieve themselves normally; it was indescribable. Frisk knew that it being Asriel doing this was likely to be frowned upon but there was nobody else they’d rather have doing it.

They trusted Asriel completely, and having him be the sole source of the intense, knotted pleasure coiled in their gut was a kind of bliss in itself. Asriel seemed to be enjoying this as well, as Frisk felt his grip tighten slightly and his movements get a little faster, a little less gentle.

Frisk was in heaven. Any concern they had about this was gone, lost in the pleasure. Having someone else touch them like this had never even occurred to them before, but now with Asriel doing such things to him, he was finally glad to have agreed. A tight, hot coil of arousal caught in his chest as he found himself struggling a little for air. His breathing rough, Frisk started thrusting slightly against Asriel.

Asriel found himself enraptured by Frisk as he continued his motions, stroking Frisk in the way he seemed to like it most. He’d never seen, or heard Frisk acting so carnally before. He hadn’t seen anyone like this, in truth, but it was different with Frisk. And knowing that he was the cause of all the tense muscles, and quiet moaning; it only made Asriel happier.

“A-Asri...please...” Frisk moaned, swallowing hard to stop themselves from drooling. At this point, Frisk found themselves nearly delirious from pleasure, their eyes closed tightly as they writhed against Asriel’s much larger form. 

“Hm? What is it, Frisk?” Asriel questioned, almost tempted to sink his fangs into Frisk’s exposed, tense neck. The caprine was unable to stop himself from becoming aroused at this point, and felt his own erection pushing up against Frisk. He’d take care of that later, right now Frisk was his focus.

Frisk kept writhing, their hips bucking up against Asriel’s hand. Their underwear felt tight and constricting now, and Frisk wished desperately that it wouldn’t rip with the amount of stretching and movement happening to it. He couldn’t help but gasp when he felt Asriel’s bulging pajamas pushed up against his thigh. “Please, just...”

Frisk grunted, moaning quietly as they struggled a little to finish their sentence. Breathing was hard, and Frisk found himself nearly gasping for air. He felt so close to reaching his peak, but something, for some reason, was holding him back. He just couldn’t figure out what it was, he was far too caught up in everything for any significant focus.

Asriel, thankfully, seemed to have got the message. The heat of his breathing was causing Frisk to shiver but the caprine knew Frisk wanted, or rather needed, more than he was getting. So, running with the temptation he’d felt before, Asriel leant into Frisk, opening his mouth slightly and dragging his long, thick tongue across Frisk’s neck. The loud, lustful gasp that it caused only egged Asriel on, so with a small, lustful smile, the caprine sunk his fangs into his younger sibling’s tense neck, causing them to gasp and moan just loudly enough that Asriel removed his fangs and the pair froze for a moment, incredibly worried that they’d hear footsteps coming to see what had happened.

A few torturously long, silent moments passed and Frisk felt Asriel exhaling deeply, and begin to grind against Frisk’s lower back. The smaller of the two hissed quietly from pleasure, feeling the heat of his older sibling encompassing him as the soft, furred hand continued it’s illicit motions.

“You’re kinda loud, huh? Did I catch you by surprise?” Asriel asks jokingly, the hand not working on Frisk’s erection now shifting up to his chest, holding him close enough that Asriel can get to Frisk’s neck with ease. Assuming that surprising Frisk like that again may completely spoil his mood, Asriel warns them before sinking his fangs into Frisk’s neck again, feeling a little guilty at how proud he felt to hear them whimper, and gasp as he continued to stroke them, as well as grinding up against them. He had to afford himself some physical pleasure from this after all.

Frisk’s breathing, by this point, was interspersed with soft, desperate moans. Whatever it was that was holding them back from climaxing had been completely shattered when he’d felt Asriel bite him. It surprised Frisk how at ease he was with this, but no longer cared. All he wanted now was for Asriel to bring him to climax, and then to talk about what was happening.

“C’mon, Frisk. I know you’re holding back.” Asriel teased, grinding harder against them as he decided to get a little more rough with his smaller sibling, using his free hand to yank Frisk’s underwear away, giving him complete and total access to do as he wished now. A small part of Asriel began to wonder what Frisk would look like beneath him. If what was happening now was any indication, he may well find out.

“S-shut up, Asri!” Frisk scolds quietly, crying out softly as they feel Asriel’s hand tighten just slightly, as well as the now more forceful grinding up against them. Frisk brings a hand up to their mouth, aware of how loud they can get when they peak, before arching his back up against Asriel. Frisk bites into their hand, moaning Asriel’s name as they push their hips forward a final time, finally reaching his blessed climax and, much to his embarrassment and Asriel’s surprise, releasing his seed rather more forcefully than either of them had expected.

Asriel slowed to gentle motions, helping Frisk ride out their orgasm as a few more ropes of cum hit the bedsheets. He felt as if he underestimated just how potent Frisk was, seeing just how severe his peaking had been. But he was ecstatic that Frisk had allowed him to do what he had, that the bond between them was that close.

“Do you feel better now, Frisk?” Asriel asks softly, nuzzling against Frisk’s shoulder as he pulls Frisk’s underwear back into place, embracing his younger sibling tightly.

Frisk panted quietly, the afterglow from his orgasm slowly escaping him as his body began to settle back to normal. The reality of the situation that had just ended finally hit Frisk, and it hit them hard. He found it difficult to breathe, his throat was tight because of what he assumed was fear.

“Frisk?” Asriel sounded a little more concerned the second time. Hopefully he hadn’t done anything wrong, but he couldn’t really tell without being able to see Frisk’s face.

“I’m okay. T-thanks, Asri.” Frisk said quietly. They weren’t quite as relaxed and okay with this all of a sudden. “I just...don’t you think that was weird?”

“Weird?” Asriel asked questioningly, gently moving his hands to hold Frisk closer to him, much as he had before the pair had slept. “What about it was weird, Frisk?”

“Wh-what about it...Asriel? You’re my brother, a-and you just stroked me off.” Frisk said, their voice quiet and audibly nervous. “That’s not normal. F-for humans, things like that are illegal.”

Asriel paused, before holding Frisk closely and gently pulling their underwear back into place. Frisk winced a little at the slight stickiness to Asriel’s hand but didn’t dare mention it.

“I hadn’t realised humans were so against it. We don’t have to do it again.” Asriel said softly, worried that he had accidently caused a problem that may not be very easy to fix. “I’m glad I was able to make you feel good, but not if it worries you this much.”

Frisk shifts slightly, and to Asriel’s relief they finally roll over, looking up and at Asriel properly.

“It does worry me. I am still human, even if I don’t really feel like one that much.” Frisk replies with a quiet sigh, resting their head against Asriel’s chest. “It’s not like it didn’t feel good. It felt great, but it...it’s you, yknow? You’re my brother, Asriel. Normally brothers don’t, yknow, get each other off.”

Asriel nodded, bringing a hand up to slowly stroke Frisk’s hair, something he’d learnt over time helped to calm the smaller sibling down. Frisk wasn’t panicked at the moment, but they didn’t seem sure of themselves and that was a good enough reason to try and help them out.

“I understand, Frisk. We don’t have to do anything like that again.” the caprine said quietly, silently grateful that neither Toriel nor Sans had come to check up on them or wake them up yet.

“I don’t know if I don’t want to, Asriel. That’s the problem.” Frisk says nervously, a quiet and almost panicked giggle escaping them. “I mean, you’re not human but that’s not a problem. Monsters are more attractive to me anyway. But you’re my brother. If Mom or Dad found out...”

Asriel tightens their grip on Frisk, smiling a little. “They don’t have to find out. If this is the only time, nobody needs to find out.” Asriel decided it was safer not to mention how he didn’t exactly want to only see Frisk as happy as that, this one time. To him, something like that was something he wanted to repeat.

“Okay. T-thanks, Asri.” Frisk smiles a little, cuddling their brother tightly. There was quite a maelstrom of complicated feelings going on inside their head right now, so the familiar warmth of Asriel’s fur and his muscular grip was a helpful, calming influence.

Asriel was surprised to find himself disappointed. He hadn’t meant anything by what he had done, it was just something to help Frisk out. Putting it aside as displeasure from seeing Frisk being nervous, he simply held tighter to his smaller sibling.

The pair stay as they are for a few long, peaceful moments, Frisk finally managed to get enough courage to speak again. “Is it bad that I enjoyed it, Asri?”

“I don’t think so.” Asriel replied softly, still slowly stroking Frisk’s hair with his large, clawed hand. “Being touched like that is meant to feel good, right?”

Frisk shifts a little, nuzzling against Asriel’s chest. “So I’ve been told. That’s the first time anyone has touched me intimately.” The admission is quiet, but not embarrassed. Frisk was finding it hard to be embarrassed after what had just happened. “It did feel good. Your hands are so different to mine, after all.”

Asriel smiled a little, trailing his hand down Frisk’s back. “You still feel tense. What’s the matter now, Frisk?” The elder sibling was deeply concerned at this point. It wasn’t like Frisk to dwell on things, even when those things were difficult to understand, or figure out. It was one of Frisk’s strengths, and one that Asriel was somewhat jealous of.

“Guilt. I shouldn’t have enjoyed it.” Frisk says quietly, still not embarrassed but very conflicted. Frisk didn’t know how to deal with conflict. “You’re not my partner, Asri. You’re my brother.”

Asriel smiled a little. “You know, I could be both, Frisk. There’s nothing stopping it.”

Frisk froze, looking up to Asriel with a very intensely confused expression. It wasn’t that Frisk hadn’t expected something like that to have come from Asriel, but it still didn’t sound right having heard it.

“What’s that look for, Frisk? Don’t you like the idea?” Asriel said, shifting his weight so Frisk wasn’t as tightly held against him. “I like the idea of being your partner.”

Frisk swallowed hard to stop themselves from making any particularly embarrassing noises. Being Asriel’s partner...it wasn’t a bad idea. Well, it was a terrible idea in a lot of ways. But it was also a very intruiging idea.

“But Mom. Or Dad. I-if either of them had any idea about what just happened, or you asking me that, then-” Frisk’s hurried, nervous words were cut short when the pair heard the bedroom door open.

“Asriel, Frisk? Are you awake yet?” The soft, motherly voice of Toriel came around the door before the woman herself walked around it, stopping in the doorway with a small, caring smile on her face.

“Morning Mom.” Asriel replied quietly, still slowly trailing his hand over Frisk’s back. “We’ll be out in a couple of minutes okay?”

“Of course, my child. Try to be quiet, if you could. Your father isn’t awake just yet.” Toriel says quietly, smiling warmly at her children.

Asriel nods, smiling back, before breathing a heavy sigh of relief when the door closes, leaving the pair of them alone again. “She’s gone, Frisk. Don’t worry.”

Frisk nods weakly, almost shaking from nervousness. “I hope she didn’t hear anything. This is weird enough without Mom being involved.”

Asriel nodded slightly. “I meant what I said though, Frisk. If you want to, I could be your partner.” He smiles a little, placing a hand against Frisk’s chin to make them look up and into Asriel’s eyes. “Would you like that?”

“Asri, you’re my brother. Just because you’re attractive. Quite...seriously attractive, that doesn’t mean it wouldn’t be weird for you to be my boyfriend.” Frisk says quietly, shuffling closer to Asriel to get closer to the caprine’s warmth.

“Then I won’t be. Let’s just figure things out slowly.” Asriel says quietly, moving away from Frisk and sitting up, moving over to the edge of the bed and looking over to Frisk, who was tiredly sitting up alongside him, leaning against his arm.

“Okay. Slowly is good.” Frisk says quietly. “But no more morning weirdness.”

“I can’t promise that, Frisk.” Asriel says teasingly, winking at their smaller sibling. “You’re so cute when you act that happily, after all.” The tired, quiet groan that got from Frisk was all the answer he needed.

\------------------------------------------

“Frisk, darling, do you mind if we talk?” Toriel’s tone was soft, and as loving as it always was, but Frisk found it rather nerve-wracking. Ever since what Asriel had done with them three days prior, the human had found themselves to be a nervous, panicking mess when they were around either Sans or Toriel, and to a lesser degree Asriel himself.

“S-sure Mom. Is everything okay?” They try to keep their tone level, but Frisk knows that Toriel had always been able to see through them. Frisk very rarely tried to lie but anything other than complete truth was basically useless against Toriel, with how strongly she was able to figure things out.

“Well, that’s what I’d like you to tell me, my child.” Toriel says, almost sounding apprehensive. It wasn’t a tone of voice that Frisk could remember hearing before, from their adopted mother at least, and it was worrying. “You seem to be very nervous. Did something happen recently? Something at school, perhaps?”

Frisk internally took a deep sigh of relief that Toriel assumed it was such a simple thing. This shouldn’t be too difficult to explain away, or so they hoped. “Things are fine, Mom. I’m not nervous.”

“Frisk. You know I can tell when you aren’t being truthful. Your brother and father aren’t here, so you do not need to worry about them hearing us.” Toriel took Frisk’s hands in her own, a deeply concerned look on her face. No amount of willpower that Frisk was so proud of would allow them to deal with the guilt of hiding the truth from Toriel.

“It’s not a big deal, Mom. Please, don’t worry so much.” The attempt that Frisk makes to move away from the subject is weak, and both Toriel and Frisk themselves know it. “Why are you bringing this up all of a sudden anyway?”

“Because I’m concerned, my child. I haven’t seen you this nervous in a long, long time. So please, tell me what has caused this. What has made you so worried?” Toriel’s soft smile broke the small amount of willingness Frisk had to resist telling the truth.

So, with a quiet and very nervous sigh, Frisk decided to be completely honest. Hopefully Toriel wouldn’t hate them for what had happened.

“Asriel. A few days ago, we woke up together. I...I was aroused.I don't know why. I just woke up like it, I guess.” Frisk couldn’t bear to look at Toriel, their speech quiet and nervous, “Asriel...he helped. No, helped isnt the word. He...touched me. I consented, but he did. He...got me off.”

Frisk pulled their hands away from Toriel’s, unable to bring themselves to look at the now silent monster across the table from them. Frisk had never truly understood what shame felt like until now. Their chest felt tight and it felt like a physical impossibility to do anything except sit there, almost waiting for Toriel to punish them, or hit them. Toriel had never hit Frisk before, but they were convinced that if anything would make that change, this would be it.

It took too long for Toriel to speak up, in Frisk’s opinion. But they were glad that she spoke rather than hurt. “And that is what has had you so concerned, Frisk? That you and Asriel did such things?”

Frisk nodded weakly, nervous and on the brink of full-blown panic. “Y-yes. He’s my brother. I shouldn’t have let him touch me. I shouldn’t have enjoyed it. I shou-”

“Frisk. My child, please listen to me. If what you did with Asriel brought you both pleasure, I see no problems with it whatsoever. Regardless of any other connections you share, if you enjoy each other in those ways, that is fine.” Toriel smiled softly, standing from her chair and walking around the table, bending down and embracing Frisk tightly.

“But he’s my brother, Mom. Even if you say it’s okay, he’s my brother.” Frisk replies quietly, only making a half-effort to return Toriel’s embrace. “I already felt bad for thinking he was attractive.”

“You say these things as if I’m not your mother, Frisk. I know you have troubles with Asriel’s appearance.” Toriel says, laughing softly as she stands, stroking Frisk’s hair gently. “I’ll allow you to figure it out with your brother. But know that I won’t judge you for your choices, and nor will your father.”

Frisk nods weakly, standing and brushing themselves down, finally gaining the courage to look at Toriel properly. “I was expecting you to be mad. I just...thanks, Mom. You’re the best.”

Toriel smiles, a faint blush appearing beneath her fur. “I’m glad you seem to think so, my child. Now, I believe I have bothered you enough for now. Your brother will be home soon, so that will give you a chance to figure things out, will it not?”

\-------------------------------------------------------------

“Frisk? You look like you’ve seen a ghost. What’s the problem?” Asriel’s voice startled Frisk, who had been listless and staring into space. The conversation with Toriel earlier had shaken them. The lack of conflict that it caused was still shocking, and Frisk had spent all the time they had before Asriel had arrived trying to figure out how to approach the subject.

“Sorry. You startled me.” Frisk looks up to Asriel, smiling softly and standing from the bed, walking over toward their larger sibling. “So. I, uhm, talked to Mom earlier.”

Asriel tilts his head a little, closing the bedroom door behind him. “You talk to Mom a lot. That’s not a weird thing.”

Frisk laughs nervously, fiddling with the cuffs of his sleeves as they shift their weight, unsure of how to stand. “It was about us, Asri. What we did. Or what you did to me, I suppose.”

That caught Asriel’s attention. “And how did that go?” His voice betrayed the nervousness he wasn’t showing physically. He may have looked calm, but Frisk saw through it, to a degree.

“Well, she wasn’t mad. She seemed okay with it.” Frisk’s demeanor calmed slightly, seeing that Asriel wasn’t exactly relaxed about things either. It was reassuring in a way. “I don’t feel quite as awful about the idea of what happened anymore.”

Asriel smiled a little, walking up to Frisk and hugging them tightly. “That’s great. Then there’s no more problems right?” Asriel hoped that he didn’t sound too enthusiastic about the idea.

“Do you really want to be with me that much, Asri?” There was a quiet, nervous hope in Frisk’s tone, that Asriel hadn’t expected. He was aware that Frisk wasn’t exactly experienced in romance, having never, as far as Asriel knew, having a romantic partner.

“Frisk, I trust you more than anybody else. I’d rather have you as my partner than anyone else I could name.” Asriel said softly, coiling some of Frisk’s hair around his fingers. “I would love to be with you. I mean, not a lot will change if you think about it.”

“It wouldn’t? But I thought there were requirements to the whole romance thing.” Frisk replied, their voice somewhat muffled by Asriel’s chest. “Like making out and, uh...more lewd stuff.”

Asriel laughed quietly, moving one of his arms and pulling Frisk up to look at him properly. “Would you like me to kiss you then, Frisk? I’ve been told I’m good at it.”

Frisk hated blushing. They always thought it made them look dumb. But Asriel loved it, if only because so few people ever got to see them like this. And there was a small coil of pride in Asriel’s chest to know that he was the one to cause such embarrassment from his younger sibling.

“I think I should take that as a yes. Unless you say no now, of course.” Asriel said quietly, pausing for a moment to allow Frisk to do so.

Frisk didn’t. Instead, as a petty act of vengeance but one that Frisk felt very gratified in doing, they wrapped their arms around Asriel’s neck and pulled him down, instigating the kiss for themselves.

To say Asriel was startled would be somewhat of an understatement. Frisk was never a particularly forceful or dominating person, so having them do something like this caught the caprine very much off guard.

Frisk wasn’t experienced with kissing. They’d never kissed anyone intensely before, where Asriel clearly had. It wasn’t exactly easy, either, with Asriel’s facial structure differing from Frisk’s own, but that didn’t detract from the pleasure it gave them.

Asriel too, found himself deeply enjoying the feeling of sharing such a sudden and forceful kiss with Frisk. He had wanted to see what Frisk kissed like for quite a while, and found himself pleasantly surprised.

The pair stayed tangled in each others arms for a few moments more, before Frisk’s inexperience forced them to pull away, unable to breathe that well while pushed up against Asriel as much as they had been.

Asriel found himself laughing softly, holding Frisk closely to him. “You don’t seem to be as reluctant anymore, Frisk.” At this point, Asriel was only half-trying to hide his happiness at the new situation that had arisen. It wasn’t as if he had been seeking to be Frisk’s partner, but he couldn’t deny that the idea of it wasn’t pleasing.

“Sh-shut up, Asri.” Frisk says, pouting slightly. “Stupid, attractive goat. You and your stupid soft fur, and your muscles, and-”

 

“I get it, Frisk. You think I’m hot.” Asriel says, laughing quietly as he lets Frisk go, stepping back from them slightly. “You seemed very eager to kiss me, too. Even if it wasn’t quite the kiss I was hoping for.”

Frisk looked somewhat confused. Their inexperience was frustrating to say the least. Frisk might not have been innocent, but they hadn’t expected Asriel to be so much less so.

“Something the matter, Frisk?” Asriel asks quietly, resisting the urge to simply take the lead and show Frisk what he had meant. But he also didn’t want to remove whatever chance he had of actually moving further with his younger sibling, so caution was paramount.

“No, nothing. I just didn’t expect you to be so frisky, Asri.” Frisk says, cursing internally at the unintentional pun. Maybe their parents really were rubbing off on them, no matter how they’d tried to resist that.

“You aren’t saying that in a way that makes me think you see it as a problem, Frisk.” Asriel replies, leaning down slightly to kiss Frisk on the forehead. “At the risk of getting slapped for the pun, would you like to get frisky, Frisk?”

Asriel wasn’t at all surprised when he got a rather forceful headbutt to the chest and a sour, embarrassed glare from Frisk. “You’re a jerk, Asri.”

“I love you too, Frisk. But that doesn’t answer my question.” Asriel says, wincing a little at the sharp pain now buried in his chest from Frisk’s reaction. “We don’t have to, don’t worry. But I’d like to, if you’re alright with it.”

Frisk sighed quietly, tightening their grip on Asriel. “I don’t know. The other day was the first time I’ve ever been touched like that. Doing more is kinda terrifying.”

Asriel nodded, before reaching down and scooping Friskup bridal-style, carrying them over toward their shared bed and lying them down upon it. “Stay here. I’m gonna lock the door.”

Frisk nodded, weakly. They hadn’t felt this nervous since they had first fallen into the Underground, all those years ago. It was very rare for Frisk and Asriel’s bedroom to ever be locked, but both Toriel and Sans knew well enough to leave whoever was in there alone while it was.

So, at least, they wouldn’t be walked in on, while they were doing...whatever they were going to end up doing. Frisk was trying not to think about it too much. It wasn’t that this wasn’t exciting, in a way. But it was equally terrifying, in another way. Namely the size difference. Asriel was huge, compared to Frisk. Frisk only just came up to Asriel’s chest, and had no real muscles to speak of, unlike their caprine sibling.

It didn’t take long for Asriel to lock the door and walk back over to Frisk, shedding his shirt on the way back to the bed, before climbing up and over his smaller sibling. The bed sunk slightly beneath Asriel’s weight, and Frisk suddenly felt much smaller than they normally did.

“So, uh, what exactly do you want to do, Asri?” Frisk asked, rather nervously. Despite the locked door, Frisk was well aware that Toriel was still in the house. It was concerning, to say the least. Not that Asriel was really letting Frisk focus, with how close he was, and how needy he looked. Frisk had never seen anybody actually look lustful before. It was a very unusual experience, and one that forced them to swallow hard, a shiver crawling down their spine.

“You, Frisk. You are what I want to do.” Asriel replies, a soft growling undertone to his voice. He found himself proud from seeing Frisk biting into their lip, most likely to stop themselves from making any noise. “I know you haven’t done anything like this before, but we should change that, don’t you think?”

Frisk pauses slightly, shifting their weight and trying to find a way to lay comfortably beneath Asriel. It took a moment after that before reality hit them and they realised exactly what was happening. They were beneath a half-naked Asriel, on their bed, and was likely to end up doing some rather lewd and perhaps incredibly pleasurable things with their large, caprine sibling.

“I’ll take that expression as a yes.” Asriel continues, leaning further down toward Frisk, a low growl in the back of his throat as he opens his mouth, his fangs bared. “You seemed to enjoy me biting you before, so why don’t we start with that?”

Frisk nodded weakly, craning their neck to expose more of the tight, twitching muscles beneath their dark skin. They didn’t exactly know why their neck was such a weak point, but they could sometimes still feel the sharp sensation where Asriel had bitten them while pleasuring them, a few days prior.

Asriel couldn’t help but smile as he saw Frisk shifting and twitching, and there was a spark of realisation in Asriel. Seeing Frisk like this was bringing about a very deep, carnal need within Asriel, and it was all the goat-monster could do to not tear Frisk’s clothes off then and there.

Asriel had expected to enjoy seeing Frisk being nervously excited, but not this much. Nor did he expect to feel such a powerful aura of need coming from Frisk. It was as if the human was silently begging them to stop waiting.

“Asri? I thought you were going to bite me. Why are you just staring at me?” Frisk asked nervously, fully aware of the intense glare Asriel was giving them.

“I’m just admiring how hot you are, Frisk. I’m honestly surprised you haven’t been beneath someone before. Or had someone beneath you.” Asriel replied, before allowing his inhumanly long, thick tongue to trail over Frisk’s neck, forcing any reply the smaller sibling would have had to be replaced with a quiet, whimpering moan.

Frisk couldn’t stop themselves from writhing beneath Asriel as he felt the heat and stickiness of his saliva coating their neck. It wasn’t even much of a thing to feel, but it was enough to cause Frisk to become achingly aroused. It worried them slightly that if something so simple as this had already begun to make them hard, what kind of reaction they would have to something more serious.

Seeing how Frisk had already begun to react, Asriel decided that wasting time would be nothing more than torture to their poor, inexperienced sibling. So with that in mind, the caprine opened his mouth and sunk his sharp, pointed teeth deep into Frisk’s neck, causing the human to cry out. It was like music to Asriel’s ears, and they had barely even started yet.

“H-how are you so good at this? I thought you were a v-virgin, Asri!” Frisk stumbles on their words, their back arching somewhat. Unable to allow themselves to simply lie beneath Asriel any longer, Frisk wrapped his arms around Asriel as best he could, holding the goat tightly.

Asriel pulled his teeth free of Frisk’s neck, gently kissing the slightly bruised area. Explaining that wouldn’t be very easy, but Asriel didn’t care at the moment. “I am. But why don’t you focus more on enjoying this and less on questioning me?”

Frisk nods, coiling their fingers into Asriel’s fur. It was incredibly annoying to Frisk that Asriel’s body was too far away to grind against. Frisk couldnt remember ever feeling such a harsh itching arousal coiled and burning inside them.

“Asriel. A-Asri, come on. Stop being a jerk.” Frisk begged, struggling to carefully remove their hands from Asriel’s thick fur, before reaching down and pulling down their fly, thrusting their hips forward slightly to push themselves free of their tight pants, if only slightly.

Asriel couldn’t help but laugh quietly at Frisk’s aggravation, moving so that he was directly atop Frisk now, “I’m not being a jerk, Frisk. I’m enjoying this, and so are you no matter what you say.”

Frisk groaned quietly, glaring at Asriel half-heartedly, causing the caprine to smile. Asriel bent his arms beneath him, now holding himself mere inches over Frisk. As Frisk had asked for more, it only felt fair for Asriel to do as he was asked.

The kiss that Asriel and Frisk had shared before had been pleasant for Frisk, if somewhat new. But the kiss that Asriel instigated this time was much more forceful and overwhelming. The short, sharp bite that Asriel gave to Frisk’s lip had caused them to open their mouth and that was when Frisk completely gave up on attempting to resist any advances that Asriel would push on them.

Asriel completely dominated the kiss, grabbing at Frisk’s hair and pulling them close, his long, prehensile tongue forcing its way deep into Frisk’s mouth.The human whimpered quietly, unable to fully react to what was happening. Not that they really wanted to. Asriel’s scent was overwhelming, and the closeness they had filling Frisk’s head full of desires that would have made them ashamed only a week before.

Asriel could practically sense Frisk’s need, at least if them being so tense and fidgety was any give away. He lingered for only a few moments, his tongue deep in Frisk’s mouth, before pulling away. His long, black tongue hung freely from his maw, causing some hot, thick drool to drip down onto Frisk’s chin and neck, the smaller sibling opening their eyes to look at Asriel properly.

“S-shit, Asri.” Frisk pants, their chest heaving slightly. They untangle their arms from Asriel, letting them drop down onto the bed. Looking down for a brief moment, Frisk now realised they weren’t the only one that was aroused at this point. Although the bulge in Asriel’s clothing seemed to be significantly larger, which was slightly worrying to the younger of the two.

“What’s the matter Frisk?” Asriel asks, nuzzling their partner’s cheek as they do so. “We can still stop if you need to.”

Frisk shakes their head, smiling happily. “I don’t want to stop. I just didn’t know that you’d get hard from just kissing me.” Their tone is teasing, but their nervousness is keeping them from doing anything more than smile at Asriel’s embarrassment. They were more than happy to let Asriel take charge anyway.

“What can I say? I’m happy we’re finally doing this.” Asriel replies, embarrassed. “But you still haven’t told me what you’d like to do. You know my intentions, but what are yours?”

Before Frisk gets a chance to properly reply, Asriel moves and peppers their neck with light kisses and bites, causing them to writhe and a quiet moan to escape from them. “C-come on, Asriel, stop being such a jerk. How can I answer you when you’re biting me like that?”

Asriel only laughs, shifting so that they’re closer to Frisk, before slowly pushing his hips forwards, his barely-contained erection grinding up against their brother’s. The shocked, lustful moan that it brings out of Frisk is plenty of reward for Asriel, but he found himself wanting more. As much as he cared deeply about Frisk, he didn’t want to keep being so gentle and considerate when Frisk was clearly just not vocalising their desires.

“You’re so sensitive. It’s almost like you want me to fuck you, Frisk.” Asriel’s voice sends shivers down Frisk’s spine, and they couldn’t stop themselves from glaring at their elder brother.

“I’ve never had someone do these things. It’s all new to me, and you’re so...big. Uh, tall. I meant tall. And muscular, too. Y-you’re just really hot, okay?” Frisk buries their face in their hands from embarrassment. They didn’t know how to deal with this, and Asriel was far from helpful with how teasing he was being. “Can we just get on with this already?”

“Not a chance, Frisk. I want to take this slowly.” Asriel pushes themselves up onto their hands and knees, looking into Frisk’s eyes. “I want us both to enjoy this okay? So don't worry. If it helps, I won’t tease you as much.”

Frisk groaned quietly, more out of frustration than anything else. This must be what sexual frustration is like, they assumed, and they didnt like it at all. “I am enjoying this, Asri. But you’re being so slow. I want to get through this but it’s so hard to do when you aren’t doing anything.”

Asriel sighed quietly, a soft smile on his face. “Well, forgive me for being considerate. Would you rather I just had my way with you then?” He wasn’t entirely joking, but Frisk didn’t need to know that. In truth, Asriel was every bit as nervous as their younger brother, he just knew more about what he was doing. Sort of, at least. Asriel found himself very glad that he’d learnt how to hide his emotions from Frisk. “I could do that, if you’d like. Just fully enjoy you, and make you squirm.”

Frisk was trying not to react too much, but they suddenly found themselves worrying that getting Asriel this needy might trigger him switching into his Hyperdeath form. He’d seen Asriel slip into it a few times, but always when he was overly angry with something in particular.

It also concerned Frisk to find that they didn’t exactly find the idea of Asriel having their way with them unpleasant. There was no way that Toriel would possibly forgive the kind of thoughts running through Frisk’s head now, no matter how much the loving goat-woman may say otherwise.

“That look in your eyes is telling me that’s what you want Frisk. Tell me, Frisk. Tell me what you want.” Asriel was almost begging for some sort of input from Frisk at this point. They’d been so passive that Asriel found himself beginning to struggle with enjoying this. 

“I can’t tell you what I don’t know, Asri. I’ve never done anything like this before.” Frisk replied softly, nervous that they were killing the mood and that whatever was going to happen, wouldn’t if they kept being truthful. “I don’t even know where to start.”

Asriel nodded, leaning down to kiss Frisk softly on the forehead. “Well, then we should probably start by getting naked right? I mean, that’ll make everything easier. From there we’ll just have to figure it out together.”

Frisk nodded, pushing Asriel’s chest gently. “Get off me then. I can’t strip with you on top of me like this. Uh...you did mean for me to strip too right? You didn’t have any weird ideas about trying to take my clothes off for me?”

Asriel smiled a little, winking and hoping that he was looking as seductive as he hoped he was. “That depends. Do you want me to strip you, or would you rather take off your own clothes?”

Frisk flushed slightly, a pale shade of pink dusting their cheeks. “D-don’t be like that, Asriel. I can take off my own clothes.” Frisk pushes harder against Asriel’s chest, but to no avail. Their brother was just too heavy and muscular to be shifted by Frisk’s less than powerful arms. “Asriel, come on! Get off already!”

The elder sibling smiled slightly, pushing himself up so his weight was pushed completely on Frisk’s stomach, both to hold them down and to allow Frisk to properly size them up. They were, after all, much larger than Frisk in a lot of ways, which he didn’t want to cause problems.

“That’s not getting off! You’re such a jerk Asri, you’re heavy!” Frisk groaned, thoroughly annoyed that Asriel was being so antagonistic to his desires. “Why are you sat on me, you, uh...” Frisk pauses, swallowing hard when this new angle fully allows them to see just how large the bulge in Asriel’s pants is. That in itself was slightly intimidating, but the rather large dark spot was proof that Asriel was clearly a lot more needy than Frisk himself, or just much more productive.

“What’s the matter Frisk? Goat got your tongue?” Asriel teased, quite content just to stay where he was. It was bizarrely satisfying to have Frisk squirming beneath them, an embarrassed mess still trying to figure out what was going on. “Or would you rather I put my tongue to some use here?”

Frisk blinked, swallowing hard as they tear their eyes from Asriel’s crotch up toward his face. “Your tongue? W-what are you suggesting, Asri?” By now, Frisk was purely playing innocent. While he was inexperienced, he wasn’t completely unaware of what Asriel was insinuating. Nor was he entirely sure how it would feel.

“Well, why don’t I show you instead of explaining? We’ve been talking so much, we should really start getting on with things, don’t you think?” Asriel says, laughing quietly before moving himself off of Frisk, slipping down between his younger sibling’s legs.

Frisk pushed themselves up onto their elbows, trying to see what Asriel was actually planning on doing, to see if it aligned with the rather hopeful ideas he had running through his head. It almost worried Frisk how into this they had become, but they weren’t entirely fazed. Maybe this was more natural than they had assumed it would be.

“I’ve wondered for a while what you taste like, Frisk. I’m glad I can finally find out. Just...try not to be too loud okay? Just because Mom is okay with this doesn’t mean it won’t be weird if she hears you.”

Frisk glares daggers at their soon-to-be-lover, but was more than willing to agree. If either Toriel or Sans heard them while anything was going on, they’d never be able to shed the embarrassment from it.

Any further reaction Frisk would have had was replaced by a short gasp as Asriel pulls Frisk’s pajama pants down, allowing their arousal to become painfully obvious. Frisk wasn’t exactly well-endowed, especially compared to Asriel, but they weren’t exactly small either. Frisk never really measured themselves, to be completely honest. It had always seemed like an unusual thing to do.

“Hmhmhm, you really are into this, arent you Frisk? And you were so nervous the other day.” Asriel muses, gently trailing a claw over the underside of Frisk’s erection, causing them to wince slightly from the sharp pulling sensation, despite it’s gentleness. “You surprised me, then. I didn’t realise you liked me so much as to let me get you off like that.”

“I was tired and horny, Asri. You just happen to be really comfortable and...really good at what you did.” Frisk admits, giggling nervously as they lie back down, closing their eyes to better appreciate the more physical side of what would happen.

Asriel smiles, a faint blush glowing through his fur as he takes Frisk’s hardon into his hand, using slow and gentle strokes to keep them aroused for now. The small twitches and shifts that Frisk made while he did it was proof enough that Frisk had succumed to desire, but Asriel wanted to see just how far they’d be willing to go. “Well, I’m going to go a little further than just stroking you this time. After all, how else can I taste you unless I do something like this?”

Frisk swallows hard, most of their muscles coiled tightly as they feel Asriel’s hot breath against their crotch, making their cock twitch with arousal. They were incredibly nervous, but Asriel was caring enough that Frisk knew this wouldnt go further than they were comfortable with.

The human was forced to bite down on their lip to muffle the moan that escaped them as they felt Asriel’s thick, drool-soaked tongue drag its way along them, a hot, tingling sensation left behind. They already felt crippled with arousal, and they’d barely even begun. That was not a good sign, in their book.

“Golly, Frisk. I barely even did anything and you’re already so turned on.” Asriel teases, letting their tongue hang out and drip drool over Frisk’s crotch. Asriel’s own nervousness was starting to kick in at this point. He’d have to be very careful not to hurt Frisk, with his fangs being so sharp and so close to a very sensitive part of Frisk’s anatomy.

“Ugh, shut up Asriel! Just get on with it already!” Frisk was beginning to get frustrated with their brother at this point. They loved him dearly, now in less pure ways than before, but Asriel still talked far too much when he had things that, in Frisk’s opinion, were much more important to get done.

Asriel couldn’t help but laugh, enjoying Frisk’s annoyance almost as much as he was enjoying making them aroused. But he was nothing if not willing to help. So, gently and slowly, he trailed his tongue over Frisk again, leaving a thin film of his pale gray drool over their arousal before taking the first inch or so into his mouth, causing Frisk’s back to arch and a much less quiet moan to come from them this time.

The taste wasn’t exactly unpleasant, but Asriel wasn’t expecting it. He found himself enjoying it though, as he closed his eyes and circled his tongue over Frisk’s most sensitive spot. They appeared to be thoroughly enjoying it, and so Asriel was as well. Taking extra care not to scrape Frisk with his fangs, Asriel lowered his head, taking Frisk deeper into his mouth, cradling more of his lover’s erection with his tongue. 

Frisk was nearly overwhelmed. The heat of Asriel’s maw combined with the hot stickiness of his drool was a far more intense sensation that Frisk had ever dealt with before, but somehow also not intense enough that it was forcing Frisk any closer to orgasm than he would have been if he was pleasuring himself. They suspected that Asriel was using some form of magic for that, not that they minded.

Asriel swallowed, his tongue tightening around Frisk for a brief moment before he decided that if he was going to get Frisk off like this, he may as well attempt it properly. Or at least, what he hoped was properly. So, uncoiling his tongue from Frisk, Asriel pushed himself down completely against his younger sibling, his snout pushed flush up against Frisk’s sweat-slicked skin as the entirety of Frisk’s achingly aroused cock was taken into his mouth. 

“S-shit, Asri.” Frisk grabbed at the bedsheets helplessly, barely able to speak through their heavy breathing and deliberately quietened moans. They were incredibly glad that Asriel had, or at least they hoped he had, locked the door so that noone would be able to walk in on this, for there would be no explanation whatsoever for this scenario.

A small part of Asriel was slightly disappointed that Frisk hadn’t tried to grab his horns, which worried the goatmonster some. He was supposed to be the one taking charge here, yet the dominant thought in his head was a wish that Frisk would grab hold of his horns and thrust into his mouth.

Doing what he could to suppress that particular way of thinking, Asriel began bobbing his head on Frisk, wrapping his agile tongue twice around their lover’s erection to, hopefully, make this better for them.

Frisk was no longer able to hold back their moaning as they felt the tight, heavy sensation of Asriel’s tongue coiling around them. Arching their back, Frisk thoughtlessly pushed their hips up against Asriel, panting and drooling slightly as they did so. They were achingly turned on, and begging for some form of release. They’d satsify Asriel as well, of course, but Frisk needed so badly to get off that it almost hurt.

Asriel tried to ignore the warm, pleasant feeling in his chest and in his groin when Frisk pushed against him. Asriel had never even thought of the possibility that he’d want Frisk to take charge with things like this, nor was he sure he wanted to entertain such thoughts. But right now what matters was Frisk, and their pleasure. Regardless of how desperate Asriel felt to get himself off, and how he could feel his own pajamas dripping from his arousal, he wanted to get Frisk off far more than himself.

“A-Asri, if you keep this u-up I won’t be able to last!” Frisk pants and groans, clawing at the bedsheets as they writhed, barely able to hold themselves back. They didn’t expect to last such a short amount of time. When they were helping themselves out, it wasn’t uncommon for Frisk to last upwards of fifteen minutes, but as far as Frisk could tell, it had barely even been five, if even that long.

Asriel smiled as best he could around Frisk’s erection, increasing the pace of his motions ever so slightly to push Frisk ever closer to the peak that both involved wanted them to reach. It was only then, however, that Asriel realised that his fur would become matted if any of Frisk’s seed hit it. He hadn’t anticipated being required to swallow it on the first time that something like this would happen. He wasn’t entirely sure that he minded, either. Which was probably worse.

The increased pace of Asriel’s motions made Frisk’s already tight chest begin to sting. They found themselves breathless from the overwhelming sensations, and it wasn’t much longer before the tight, hot coil of arousal in Frisk’s lower half quickly untied itself, and with one final, unintentionally forceful thrust of their hips, Frisk finally peaked, a half-dozen offwhite jets of his seed hitting Asriel’s tongue and the back of his throat, causing the caprine to reflexively swallow, the bittersweet sticky fluid clinging to the insides of Asriel’s throat as he slowly pulls away from Frisk, swallowing down the last of Frisk’s cum before climbing back up over the smaller human, kissing them softly to share the taste.

Frisk melted into the kiss almost on instinct, lazily bringing their arms around Asriel’s neck. To say that Frisk was blissful would be an understatement. In this moment, bathing in the afterglow of an orgasm brought on by someone they had never expected, Frisk felt completely and totally in love. And, when they realised that, it scared them. Up until now, Frisk didn’t even fully believe they were capable of romantic love. And now, to feel it for their older, monster brother? It felt both completely perfect and intensely wrong at the same time.

But Frisk was okay with that. The love they felt for Asriel was the strongest, most heartfelt emotion they had had since the pair had fought in the Underground, where Frisk had SAVED all of their friends and adopted family.

“I love you Asriel.” Frisk said when Asriel pulled away from the kiss, a small trail of drool hanging between them. “I’m glad that you were my first.”

Asriel smiles softly, nuzzling against Frisk’s cheek. “I love you too Frisk. And I’m glad that you trusted me enough to let me be that first.” The goatmonster then let one of his arms fall beneath him, so he was laid beside Frisk on the large bed, cuddling up to their younger sibling. “Perhaps another day you can do the same to me, huh?”

Frisk rolled onto their side, shifting back so that their back was flush up against Asriel’s chest. They had hoped that they would have been able to do such things now, but the physical exhaustion that was setting in due to what had just happened meant it was all they could do to stay awake, despite it only being mid-afternoon.

“I will, Asriel, don’t worry.” Frisk’s voice is soft, and quiet as Asriel pulls them close, softly stroking their lover’s hair. 

The caprine smiles gently, planting a soft kiss atop Frisk’s head. “I’m not worried Frisk. Although I suppose this makes us more than just siblings now, doesn’t it?” Asriel laughs quietly. “What do you say, Frisk? Would you be alright being partners? That is the right word, right? Since, yknow, you wouldn’t be my girlfriend. Or boyfriend, either.”

“Partner is fine. Or datefriend, I guess. And yes, Asri. I would be more than happy to be your datefriend.” Frisk says, a small, kind smile on their face. Their heart was racing, but they also felt an intense wave of calm. Regardless of whatever else was going on, they had Asriel. They had always had Asriel, and now the pair were closer than they had ever been and both of them were significantly happier for it.

“Now, I guess we just have to hope that Mom and Dad didn’t hear you moaning huh?” Asriel spoke barely above a whisper, causing Frisk to freeze.

“Let’s hope so.”


	2. Preparations for Prom

**Summary for the Chapter:**

> A few days after Frisk and Asriel's experiment, things between them start to stabilise into a relationship of sorts.
> 
> Toriel and Sans see fit to, as parents should, interfere without telling either of their children.

**Notes for the Chapter:**

> Hey. Aithe here. I'm glad to see that the first part of this was received well, especially considering this fic is the first thing I've ever posted online. So, as before, constructive criticism is welcomed as is any feedback on what you'd like to see? Jeez, I'm not good at this yet.

“so, frisk.” Sans spoke up over their shared lunch, both Toriel and Asriel had gone out grocery shopping, so Sans had decided that while they were gone, he would spend some time with Frisk.

The human looked up curiously, swallowing down the mouthful of food they had. “Yeah, Dad? What’s up?” Frisk did what they could to keep their voice level. They’d been incessantly nervous around both of their parents ever since what had happened between themselves and Asriel; despite knowing that neither of them were against it, it was still difficult to feel completely at ease.

Sans leant back in his chair, his arm hanging lazily over the back of it as he looked toward his younger chid, the ever-present grin on his face. “you’ve been using condoms right?”

Frisk locks up, a very sudden rush of heat springing up in their face as they stare directly at Sans, trying their best to not look like they wished they could just curl up and die from embarrassment.

Sans, to his credit, didn’t break out into laughter as his immediate first instinct told him he should. Instead, he pulled his arm over and pulled his chair closer to the table, pushing his plate aside. “i’m serious, frisk. you’re not a monster like us after all. and i sure don’t know how that kind of thing works between a human and a monster.”

Frisk swallows hard, their mouth and throat suddenly feeling dry as they shift uncomfortably in my seat. “Dad, me and Asriel haven’t...done anything that needs them. And even if we had, he’s a monster and I’m not female. He couldn’t impregnate me.”

Sans pauses for a brief moment, before nodding. “that makes sense. i mean, no offense kid, but we only need one mom-ster in this house. so let’s not have you or asriel becoming one too.”

Frisk groaned quietly at the inevitable pun, but felt their ears perking at the rest of what Sans had said. “Wait, Asriel? But Asriel’s male. How could he make a child? Is this a monster thing I’ve never been told about?”

Sans leant forward, resting his elbows on the table. “i thought tori would have told you about this by now. especially considering that you and asriel are up to so much recently.” Noting Frisk’s embarrassment, Sans decided to try and be as tactful as he could, even if that wasn’t exactly his specialty.

“so, kid. monsters don’t make their kids inside them like you humans do. we can still do all the stuff humans do that makes them, just, y’know, without the possibility of accidental children. monsters have their children when they really, really want them. because we’re made of magic, it’s like we siphon of some of our own, into a new monster. that make sense?”

Frisk leant back a little, feeling rather surprised they didn’t know something so basic about the people they called their family, or their people considering Frisk was connecting less and less to humans over the years. “But I’m not a monster, Dad. Even if I wanted a kid with Asri, I don’t have any magic to give to that process.”

“that might be true now, kid, but do you seriously think you’re gonna stay magic-less forever? with me, tori and asriel around you all the time i’m surprised you haven’t already accidently set the bedsheets on fire. or given asriel a different kind of bone than he was expecting.”

Frisk blushed again, burying their face in their hands, muffling their voice somewhat. “Dad, eww! You have to make things gross don’t you?” Despite their frustration, they were glad to learn something. It made Frisk wonder if that meant any two monsters could have children, if they didn’t require a biological component like humans did.

Sans relaxes back in his chair, happy to see that Frisk wasn’t bothered by what he’d said. His concerns were genuine, after all. Even if Frisk hadn’t learnt how to channel magic, there was so much of it in the household that Frisk must have absorbed some of it. They had always had a talent for doing that, Sans had noted. After Frisk had fought Hyperdeath Asriel, Sans knew he wasn’t the only one who must have noticed how the human’s eyes seemed to have looked a little more colorful, and star-shaped than they normally did.

Frisk’s embarrassment, much to their relief, faded rather quickly, and they lowered their hands, breathing deeply to calm their overly fast heartrate. “I always thought I’d get ‘the talk’ from Mom, not from you.”

Sans nodded, looking as serious as he could with a constant grin. “i expected her to tell you, kid. she’s normally good with that kind of thing. maybe its just her job thats been keeping her busy, even if we’re on break right now.”

Of course. Frisk had completely forgot that Toriel was still working on things for her school. Frisk had helped where they could, but it only made sense that their mother had been too busy for unneccessary things like that.

“don’t look so worried, kid. you and asriel are happy right?” Sans asked, expecting the nod that he recieved as answer. “then there’s nothing to worry about. just so long as you don’t end up failing classes because you’re too busy with him.”

Frisk glares at Sans, half-tempted to throw their food at him as they swallow down another mouthful. “Dad, stop. You make it sound like we’re always having sex. We haven’t even done that mu--I’m not having this conversation. I’m not talking to you about my sex life, that’s weird.”

“not weird to me, kid. at least you don’t have to worry about getting fur caught in your bones. yours are all hidden inside.” Sans spoke frankly, his eye glowing blue as he caught the incoming plate of Frisk’s lunch in a blue glow, setting it down carefully on the table.

“You’re gross, Dad.” Frisk said, a smile on their face despite it. It might have been embarrassing, but Frisk was glad that Sans was always willing to talk and listen about the kind of things that Toriel shied away from.

“you still love me though, kid.” Sans says, standing from his chair and grabbing Frisk’s plate, trashing the little remaining food and dropping the plate itself into the sink. “now c’mon, we gotta go meet up with the others.”

Frisk stood, tilting their head slightly in confusion. “We do? Why?”

Sans turned, leaning back against the counter. “if i told you that, it wouldn’t be much of a surprise, would it? now go get dressed.”

Frisk was about to protest when they felt themselves getting lifted from the floor and out of the kitchen, the door closing firmly behind them. Knowing better than to try and find out more, Frisk trudged up the stairs to their bedroom, opening the wardrobe and taking out some clothes, their body completely on autopilot as they tried to think up what kind of surprise could possibly be waiting for them.

As far as Frisk was aware, there was nothing worth celebrating. There were no birthdays recently, or anniversaries or anything. So Frisk assumed it wasn’t a surprise party of any sort.

As they pulled their head through the shirt they had grabbed, Frisk realised that it felt rather large on them. Looking down, Frisk felt a rush of embarrassment as they saw that they’d taken some of Asriel’s clothes instead of their own. They couldn’t figure out why that was embarrassing, it was just clothes.

Quickly pulling the shirt back off, Frisk hung it back up in the wardrobe and took one of their own shirts down, putting that on before grabbing some leggings and adorning those as well. The heat in Frisk’s cheeks slowly starting to dissipate, they began to wonder if this surprise they were being pulled to had anything to do with the upcoming prom at school. It was Frisk and Asriel’s last year there, after all, and prom was only a month or so away. Frisk hadn’t planned on going, but perhaps now that they were with Asriel, Toriel had decided that they would have to go.

“c’mon kid, what’s taking you so long? you don’t wanna be late, do you?” Sans’ voice came from just outside the door, causing Frisk to jump, their heart racing from the shock. It was so hard to relax when their father was so capable of moving completely silently around the house.

Thankfully, they were already dressed, so Frisk opened their door, completely unsurprised to see that Sans wasn’t there, and had somehow gotten back downstairs without any noise. “So, where are we meeting them?”

Sans shrugs, grabbing his keys and opening the door, letting Frisk leave before doing so himself, closing and locking it behind him. “can’t tell you that either kid. surprises are meant to be, yknow. surprising.”

Frisk sighed quietly. They weren’t much of a fan of surprises, they much preferred to know what was happening around them. But they also knew better than to try and get any information out of Sans that he wasn’t willing to share. Sans’ stubbornness was the only thing Frisk knew was able to outlast their own Determination, after all. A small smile came to their face as they remembered their first Christmas as a family, where Frisk had begged Sans to let them stay awake to wait for Santa, and the back-and-forth had lasted so long that Frisk passed out from tiredness almost seven hours later.

“you wanna take a shortcut or walk there, frisk?” Sans’ voice brought Frisk out of their reminiscing, as the two began to walk. “i don’t mind using human speed if you want to.”

“I don’t mind, Dad. If you want to get there faster, we’ll use shortcuts. I’d rather not get Mom mad for us being late after all.” Frisk replied, a small shiver going down their spine. Toriel never really got mad, but even mild annoyance was a lot more threatening when it was coming from your mother. Even more so when your mother was almost three feet taller than you.

Sans merely nodded in agreement, walking with Frisk into a side alley, before turning a corner and disappearing with them. Frisk always found Sans’ shortcuts to be incredibly bizarre, as nothing ever really seemed to happen. One second they were walking in one part of town, and the next they were in a completely different part of town without actually crossing any space between the two places.

“you’re getting good at walking with me through these, kid. you don’t even look dizzy anymore.” Sans said, and Frisk swore that they heard something like pride in Sans’ voice. It was true, Frisk had difficulty with the shortcuts the first few times that they’d used them with Sans. Dizziness and headaches normally. But after this long, nothing really happened anymore.

“I guess I’m just used to them by now. Shouldn’t we keep going?” Frisk said, nervous to get this over with so they could find out what was going on. A faint flush came to their cheeks as their thoughts immediately went back to the assumption they had already made, that this was something to do with the prom. Which meant that Asriel would be wearing a suit.

Trying their hardest to keep their thoughts pure and trying twice as hard to not imagine how Asriel would look in a suit, Frisk stayed mostly silent for the rest of the short walk, only offering short answers to any questions Sans threw at them.

“alright, here we are.” Sans said finally, much to Frisk’s relief. Pulling their eyes up from the floor that had become very interesting to the human since they’d left the shortcut, Frisk found themselves in front of a store that exclusively sold formal-wear, for events such as weddings, or proms.

“Crap.” Frisk cursed quietly, all of the barely-clean thoughts about Asriel in a suit immediately clouding Frisk’s mind. Looks like they were right, but they weren’t sure that was a good thing. “Mom made you bring me here?”

“yup. gotta make you look handsome for prom, kiddo.” Sans replies, nudging Frisk in the arm. “how else are you gonna shame everybody there by being the best couple at the event?”

“C-couple? Asriel’s getting a suit here too?” Frisk said, painfully aware that they were embarrassed simply by thinking about that. Embarrassment was becoming far, far too common for Frisk’s comfort. “I really wish Mom had told me this would be going on.”

Sans smiled, pushing Frisk in front of them and into the store. “no use waiting kid. just try not to get too hot for asriel when you see him.” The skeleton couldn’t help but feel happy when he was with Frisk like this, especially now that he had a new, constant source of ways to tease the young human.

It was all light-hearted and harmless, of course. Sans meant nothing by it and was in fact very pleased that Frisk was so happy with Asriel. The human had always had trouble being around other humans, ever since they’d left the Underground together. So Sans wasn’t in the least bit surprised that Frisk would eventually choose a monster as their partner, even if it being Asriel was somewhat surprising at first.

Frisk somewhat reluctantly walked further into the store, gripping tightly at the cuffs of their sleeves as they looked around. All the outfits in here seemed so expensive that Frisk desperately tried not to touch anything out of fear of accidently dirtying the fabrics or something similar.

After a few very nervous moments, Frisk spotted Toriel, who towered over even the large displays that the store held. Sans, as per usual, had completely disappeared so Frisk made their way over toward Toriel, a tight and nervous pain gripping their chest. If this was really the shop that Toriel wanted Frisk and Asriel’s prom outfits to be bought from, Frisk was even more sure that they didn’t want to go to the event. If anything in here was half as expensive as it looked, Frisk simply couldn’t allow their mother to spend so much on something so pointless as prom suits.

Toriel seemed too pre-occupied with something that Frisk couldn’t see to notice the small human approaching them. Frisk assumed that Toriel was fussing over a particular, slightly smaller goat; which of course only tightening the hot pain in their chest. If Asriel was here, and in one of the very beautiful suits that had lined various aisles of this store, Frisk wasn’t sure their SOUL could take it.

So, as Frisk got closer to where Toriel was, they decided to stay just out of sight, listening into a conversation that became audible as they closed in.

“Don’t be like that, Asriel. I’m sure Frisk will think you’re very handsome.” Toriel’s voice was as kind and motherly as ever, but Frisk could tell she sounded tired. She must have been overworking herself again.

“M-mom! This isn’t about making me look good for Frisk. All these suits are far too expensive.” Frisk smiled softly upon hearing that Asriel, for of course it was Asriel, seemed to have the same concerns they did.

“Asriel, my child, I would not have brought you here if I was incapable of affording them. Or is the problem that you would rather wear a dress?” Toriel chided, taking perhaps a little too much pleasure in how much she had flustered her child.

Frisk could already feel a serious spike in heat just behind their nose at the mere mention of Asriel wearing a dress. They swallowed hard, before taking slow and measured breaths to try and calm themselves down. There was no way that they’d be able to explain to Toriel or Asriel why they arrived with a nosebleed, after all.

“M-mom, don’t be like that! I don’t have the physique for dresses, you know that. Frisk would look much better in a dress than me.” Frisk froze, covering their nose as they felt the heat drive itself home, a fuzzy sensation filling their head as a few drops of hot, crimson blood dripped into their hand.

Frisk cursed internally, rummaging around in their pockets for something to help stem the flow of the blood before it became a problem. They gave a quiet sigh of relief as they found some tissues, holding one up against their nose as they tried desperately not to think of how attractive Asriel would find them in a dress, and what kind of situations that would create between the pair.

“That may be true. Frisk’s figure is much more feminine than yours, after all.” Toriel said, seemingly thoughtful which made Asriel laugh nervously, looking up and into his mother’s eyes.

“Mom, I was kidding. I wouldn’t expect Frisk to wear a dress to prom. They don’t even want to go, remember?” Frisk was glad to hear that Asriel was watching out for them, but was infinitely more glad that the bleeding seemed to have stopped. So, despite the clinging heat in their face, Frisk screwed up the tissue and put it in their pocket, before taking a few deep breaths and walking around the corner of the aisle, toward where their mother and sibling were talking.

“Ah, Frisk. We were just talking about you.” Toriel speaks up kindly, and Frisk was glad to hear that it didn’t seem like she knew Frisk had been hiding for the past minute or so. “I apologise for not telling you about this until now, but I wanted it to be a surprise.”

Frisk smiled weakly, internally panicking that the heat in their face was showing up as a blush or something similar. “It’s okay, Mom. But, isn’t this place for proms and stuff?”

Toriel nodded, a small and loving smile on her face. “You didn’t think I’d let you get away with not going to prom, did you?”

Frisk paused, looking everywhere but at Toriel, which meant that their eyes settled on Asriel, who was trying on a very well-cut navy blue suit, with a white shirt and equally blue tie. Frisk swallowed to stop themselves from gasping. They were finding it difficult to even think of a word fitting of how they thought Asriel looked. Gorgeous was the first one that came to mind.

Frisk was broken from their stupor by Toriel laughing softly. “Oh dear, it seems we found a suit that is too good on you, Asriel.”

Shaking their head, Frisk blushed deeply as they pulled at their sleeves. “Mom! Don’t embarrass me like that!” Not that Frisk was going to deny what Toriel had said, of course. Asriel was incredibly attractive in a suit, after all. But that didn’t make it less embarrassing to have it pointed out.

Asriel, to his credit, at least looked as embarrassed as Frisk felt. “U-uh, hi Frisk.” Asriel sighed internally, wondering why all of the smooth-talking he was capable of seemed to completely disappear whenever he actually needed it.

Toriel found herself slightly tempted to simply leave the children be, but she was here for a reason and now that Frisk was here, there was no reason to stop at just finding Asriel’s outfit. “Frisk, my child, if you can bare to look away from Asriel for a moment, I would like you to help me decide your outfit. You need to be a suitable date for your new boyfriend after all.”

It was all Frisk could do not to curl up and die from embarrassment right then and there. As happy as they were with Asriel, the constant teasing from Toriel and Sans would always, without fail, cause them such intense embarrassment that it was nearly a physical pain. Frisk knew it was only because their parents were happy for them, but that didn’t make it any easier.

“I’m glad you agree. Now, Asriel, I need you to behave while I take Frisk to find their outfit, understand? And no following us around. It’s enough of a shame that they’ve seen your outfit before the prom itself.”

Frisk couldn’t help but notice that Toriel hadn’t said the word suit, she’d said outfit. Frisk suddenly realised that they were overthinking everything. It was probably nothing and wasn’t likely to have anything to do with their mother very likely thinking about getting them a dress to match Asriel’s suit.

Frisk wasn’t very good at this whole denial thing, they realised. Sighing quietly and resigning themselves to the admittedly very likely event of being guilt-tripped into the prettiest dress Toriel could find, Frisk found themselves following Toriel around the store, a glazed look in their eyes.

“Now now, Frisk, what is that dour look for? I hope you aren’t mad that I stopped you staring at Asriel.” Toriel says, noting how Frisk, who had seemed very happy mere moments ago seemed to have changed very rapidly.

“You’re taking me toward the dresses, Mom. Can’t I wear a suit like Asriel?” Frisk says, their voice quiet and nervous. They didn’t want to upset Toriel, if she’d planned on having Asriel in a suit and Frisk themselves in a dress. Frisk wasn’t against dresses, their figure was certainly fine for it and they’d never had body hair to speak of so that wasn’t an issue.

“Well, of course you can. I just thought that you would look adorable in a dress. And I’m sure that Asriel would agree.” Toriel sounded a little apprehensive, despite herself. It was true that she thought Frisk would look good in a dress, but hadn’t realised it might be a problem. Unlike Asriel, Frisk had never opted towards a particular set of clothing, they had always worn what was comfortable.

Truth be told, she was also aware of Asriel’s jealousy that Frisk was able to wear such a wide variety of clothes whereas Asriel’s figure was a hindrance in doing so. Perhaps that was why Frisk wasn’t quite as willing to don a dress as Toriel had hoped.

“I don’t want to stand out too much, Mom. I’ll already stand out a lot by going as Asriel’s date, because we’re siblings. If I turn up as his date in a dress...” Frisk trails off nervously. They’d never been bullied per se, but they were well aware of what people thought about them. The human child of the monster family. The favorite of the principal. There was a lot of reason for the other students, monster or human, to dislike them.

“I understand your concern, Frisk. But I will ask you at least look at what is on offer. We can absolutely find you a suit if you would prefer, but at least humor me my child.” Frisk knew that, despite how kindly Toriel was speaking, that they didn’t really have much choice in the matter.

So, against their better judgement, Frisk allowed Toriel to take them over toward the area of the shop that was filled with various dresses instead of suits. As much as Frisk didn’t want to admit it, the dresses were all gorgeous, in a variety of ways. Some were very ornately decorated, others were very simple, but all of them put any dresses Frisk had ever worn to shame.

“You seem nervous, my child. Is it really such a problem for you to go with Asriel to the prom? I cannot imagine that it’s a rarity for couples to go as each other’s dates.” Toriel said, not entirely unaware of the particularly unique situation her children had found themselves in. “Nor is it too rare for humans and monsters to go as dates.”

Frisk sighed quietly, gently passing their hand over the soft fabric of some of the dresses. “I know, Mom. But it is rare for someone to go with their brother as their date. And...I can’t imagine it would go down well if anyone caught us kissing. Which we would, because it’s prom and you have to.”

Toriel smiled softly, walking up behind Frisk and placing a large, soft hand on their shoulder. “Frisk, if anybody has problems with you and Asriel, they will have to take it up with me. I may be principal of the school, but I am first and foremost your mother.”

Frisk nods after a short pause, looking up to Toriel with a somewhat unsure expression. “Thanks, Mom. But do you really think me going in a dress would be okay? Asriel wouldn’t be embarrassed with me wearing one?”

Toriel laughs softly, walking with Frisk further down the store aisle. “I doubt that very much. In fact, he may prefer seeing you in a dress. Who knows?” Toriel was, if she was completely honest with herself, actually more curious than Asriel about how Frisk would look in a prom dress. But Frisk didn’t need to know that, and it was an endless source of pleasure for the goat-woman to try and tweak Frisk and Asriel’s relationship in small, innocent ways.

“But...well, I suppose it is more traditional for one of each couple to wear a dress. And since I can, I probably should.” Frisk, to their credit, tries to sound at least slightly enthusiastic about the idea. But even for Asriel, the human finds it difficult to think that wearing a dress to prom would be anything but a bad idea.

“It isn’t a requirement, my child. If you truly do not feel comfortable wearing a dress, we can look through the suits. Perhaps find you one that matches or compliments Asriel’s?” Toriel was beginning to feel a pang of guilt in her chest, for bringing Frisk here, both to the store and the dress aisles.

“No. If Asriel is wearing a suit, I should wear a dress. And besides, maybe it will look nice.” Frisk felt like they were working on autopilot to avoid embarrassing themselves, but they did, in their way, silently wish to see what they would look like in one of these dresses. And also, much more silently, hoping that Asriel would think they were pretty.

“I’m sure it will, Frisk. Now, would you mind looking around for yourself while I try to find your brother and father? They must have wandered off.” Toriel was looking around over the railings, but somehow the others seemed to have disappeared from her view.

“Of course, Mom.” Frisk said, only half-focusing on what Toriel was saying as they scanned over the dresses. Asriel’s suit was a dark, navy blue if Frisk’s memory was correct, so the dress would have to be a similar color. All they had to do was find one that looked pretty, wasn’t too expensive, and would make Asriel proud to have them as their date. They cursed under their breath, hoping that many requirements wasn’t too many.

After a few minutes of searching, Frisk’s patience, legendary as it was, was really starting to stretch too thin. There were no dresses at all that would work. None of the blues were close enough to Asriel’s suit. And even if they had been, none of them were pretty enough. There’s no way that Asriel would approve of seeing them in any of these dresses.

Stepping away from the railing, Frisk pulled at the hem of their shirt, breathing deeply and counting how long each breath took. They felt more disappointed than they had expected about not being able to find a dress.

“Frisk?” At the sound of their elder sibling’s voice, Frisk couldn’t stop themselves from flinching. They winced internally, turning on their heel toward Asriel, who was stood at the end of the aisle. “Didn’t you find anything? You’ve been over here for fifteen minutes already.”

Frisk scratched at the back of their neck nervously, pushing some hair away from their face. “Sorry Asri. I couldn’t find any that matched that suit you’re getting. I, uh...I guess I’m going to have to buy a similar suit.”

Asriel smiled softly, walking up to Frisk and taking the human’s hands in his. “Frisk, you’ll look great no matter what you wear to prom.”

Frisk blushed heavily, looking away as their hair drops back into place. “I want to look perfect, Asriel. Great isnt enough, I have to match up to you. So I need to be perfect.”

Asriel pulls Frisk closer, hugging them gently for a moment. “C’mon, Frisk. Anything you wear will make you look perfect to me.” The caprine couldn’t help but smile at the annoyed glare Frisk gave him as response. “I mean it. Let’s look together, alright? That way you can actually ask me if I like it.”

Frisk nodded, a small but genuine smile on their face. “That sounds like a good idea. Too good for you, big bro. Mom set you up for this didn’t she.”

“Absolutely. Now, dresses?”


	3. The Obligatory Prom Chapter, because they're in highschool and I couldn't resist.

**Notes for the Chapter:**

> Hey, Aithe here. i'm not so sure how good this chapter is compared to the others, because it's been a long time since I wrote any proper smut that's more than just handjobs and oral. So, any criticisms or feedback would be very greatly appreciated. Hope you enjoy!

“you look great, kid. stop worrying so much.” Sans was trying not to show how exhausted he was getting at Frisk’s overly worried and paranoid nature, but his patience was wearing thing. Asriel and Toriel had left hours ago to start the final preparations for the prom, and Frisk had been a bag of nerves ever since they’d left.

It didn’t help matters much that Sans had no idea how dresses worked, so trying to reassure that Frisk’s looked great on them, while true, wasn’t working very well either.

“Dad, I’m allowed to be worried. What if the dress doesn’t look right when I get there? What if some people think I look stupid because I’m wearing a dress? Or what if people look at me weird because I’m Asriel’s date? I mean, it’s not like he’s the most attractive monster in the school or anything and he turned down at least a dozen offers to go with me.” Frisk found that pacing helped, so they’d be walking in a very uniform line across the kitchen for at least half an hour. Long enough that their legs were starting to hurt anyway.

Sans, desperate to try and fix this so as not to ruin multiple people’s evenings, walked to Frisk and grabbed their arms, looking up slightly so that he was looking into their eyes. “frisk. kid. listen, it’s like tori said. if anyone screws with you, they’ll have her to deal with. and if they try anything more than that, they’ll have me to deal with.”

Frisk smiles weakly, wrapping their arms around Sans and his omnipresent fluffy hoodie. “Thanks Dad. I, uh, guess we should be going right? It’s quite a long walk to school, and I don’t want to be late to my only prom.”

“walk? kid, i have a motorbike.” Sans looked as confused as his constant grin allowed him, which forced a still-flustered Frisk to continue.

“Yes, you do. But I’m not getting on a motorbike to get to prom. My dress will be ruined.” Frisk realised, subconsciously, that they were starting to sound more and more like Toriel, in their mannerisms and vocal tones. They weren’t sure whether that was weird or not.

“fair point kid. we can always take a shortcut. saves us time and, since you’ve been walking in place for forty minutes, you should probably rest your legs. unless, of course, you’d like to step on asriel’s paws when you’re dancing with him.”

Frisk sighed quietly, conceding that Sans was right and they’d have to conserve energy if they wanted to dance as well as they could. And also deal with how inevitably smug Toriel would be for all the ballroom lessons she had given them and Asriel actually having a use, despite neither of them having believed that to be true.

“c’mon, kid. turn that frown upside down, you’ve got a hot goat to go to prom with don't you? you need a smile for that.” Sans let Frisk’s arm go, punching them lightly in the chest. 

“I get it, Dad. Just as long as you don’t start trying to sell hot goats when you run out of hotdogs.” Frisk replied playfully, their mood at least restored enough for them to not be too annoyed at their father’s teasing.

“hey, that’s a good idea kid. should’ve thought of that one myself.” Sans starts to walk, Frisk following close by as they leave the house together, the pain in Frisk’s legs now reduced to a dull ache, weak enough that they’d be able to dance just fine, provided it wasn’t too often or for too long.

“Well, as long as you credit me and give me a cut of the profits, you can use it Dad.” Frisk replies playfully, walking with Sans to the shortcut he often used that was hidden just behind their family home, that connected to a side alley not far from Dreemurr High for Monsters and Humans. Frisk always, without fail, cringed at the name that Toriel had given the school she ran. She seemed to have Uncle Asgore’s awful naming ability, after all.

“turning into a business type already kid? don’t tell tori, she wants you to teach at the school.” Sans grinned, taking Frisk’s hand and walking with them through the shortcut and re-appearing a mile or so away, far closer to their destination. He let out a quiet sigh of relief when he saw that neither his suit or Frisk’s dress got damaged or warped at all while travelling. Not that it was common, but sometimes clothes changed color or ended up backwards somehow. Sans always put it down to glitches in the system.

“Ugh, don’t remind me. I’m just glad I still have time to talk her down from th-” Frisk cuts themselves off, swallowing hard as a blush so intense it almost hurts rises to their face. Their eyes were firmly locked on Asriel, who appeared to be waiting for them in front of the school gates. He was easy to spot because of his height, but he looked so imposing and powerful in the lighting from the school behind him, his sillhouette cast across the street, that Frisk almost found themselves rooted to the spot as their hand slips free from Sans’.

“kid?” Sans questions, turning around to see Frisk staring across the road at Asriel, who didn’t look like he’d noticed them yet. And Sans recognised the expression that Frisk was currently wearing too; one incredibly similar to how Sans knew he would have worn the first time he saw Toriel if he was capable of expression as severe as humans were. “kid. kid, wake up. stop staring so we can go meet him.” Sans waved a hand in front of Frisk’s eyes, snapping them out of their embarrassed stupor.

“I-I wasn’t staring!” Frisk complained, well aware they were and that denying it was completely pointless. But it was the principle of the matter, and Frisk felt they had to at least attempt a denial.

The pair walk over the busy street the first moment they get the chance, Sans patting Frisk on the back and wishing them a quiet “good luck, kid” before seemingly disappearing into thin air. Frisk would never udnerstand how he was capable of things like that, but they didn’t have time to think about that, they had a date to meet. A very tall, very imposing and very handsome date.

“U-uh, hey Asri. Sorry that I’m a little early, Dad brought me here through-” Frisk’s voice was quiet and a little nervous as they waved at Asriel while approaching him. Their heart sunk when they saw a very, very pretty fire-girl talking to Asriel and looking intensely offended that Frisk had spoken to the goat-monster. They swallowed hard, bowing their head in apology. “Am I interrupting something?”

“Howdy Frisk! And not at all, we were just talking.” Asriel smiled at his date, internally incredibly happy that Frisk had arrived when they had, as the fire-girl had been hounding him for a while now and he couldn’t find it in his heart to simply end the conversation. However, Asriel had been thinking up the perfect way to end it and now that Frisk was here, he could do so.

Frisk smiled nervously at the fire-girl, silently panicking that they had come at the wrong time and that they’d stopped something happening between her and Asriel. Not that they thought Asriel would abandon their date or anything, but Asriel was too kind ofr his own good at times.

As a result, they were intensely surprised when Asriel approached them, bending down and kissing them, a kiss that was just passionate enough to prove to the fire-girl that Frisk was his date and there would be no alternatives. Frisk closed their eyes, kissing back a little less enthusiastically before pulling away, their chest tightening when they realised that the girl hadn’t left, and in fact looked furious that Frisk was here at all, as if Asriel had been stolen from her.

“Seriously, Azzy? Of all the choices you could have, you chose this one? No wonder you’re single if your preference is emotionless humans” The fire-girl’s tone was harsh, and any pleasant mood Frisk still had was completely replaced with a heavy sadness.

“Please, Naya, show some respect. Frisk is my date, not you. Jealousy is an ugly trait to have, you know.” Frisk swallowed hard as Asriel defended them, their hand being gripped tightly in the goatmonsters as Frisk looked up to Asriel, who seemed to be locked in a staring match with the girl, who Frisk now knew as Naya.

“Jealous? Please, I’m not jealous of them. I’m just shocked that you’d have such poor taste in dates.” Naya’s toen was even more harsh than before, and her gaze shifted to Frisk, who felt themselves shrinking against Asriel.

Asriel sighed quietly, silently a little frustrated that kissing Frisk in front of Naya hadn’t worked in making her leave, and also struggling to contain his anger at the girl for directly insulting Frisk in front of him. “The most attractive human in school is hardly poor taste, Naya. You don’t have to like it, but Frisk is my date. And for the record, I’m not single. Frisk and I are dating.”

Frisk bit into their lip, a horrifically red blush rising to the roots of their hair. They’d never actually confirmed with Asriel if they were proper romantic partners yet. They hadn’t even gone on a real date, after all.

Frisk also found a sick kind of satisfaction in how outraged Naya looked at the mere mention of such things. That wasn’t something they were proud of but it wasn’t possible not to notice the pleasant heat in their chest from it.

“Now, if you don’t mind, my partner and I have a prom to attend.” Asriel said, his tone authoritative and almost harsh as he half-dragged Frisk away and into the school itself, pulling Frisk aside to a quiet and unused corridor. “Sorry about that, Frisk.”

“You don’t have to apologise for it, Asri. It’s alright.” Frisk swallowed hard, noticing that Asriel was very close and their back was almost against the wall. If Frisk didn’t know better, which they seriously hoped they did, this kind of situation would normally end with Asriel making out with them at the very least.

Frisk was trying not to think about the more intimate things this could lead into when they felt Asriel nuzzling against their cheek. “I couldn’t ask for a better date, Frisk, no matter what others say. And, as I haven’t had the chance to say it yet, you look incredible.”

Frisk blushed even harder, if that was possible, stepping back against the wall as they covered their face with their hands. “S-shut up, I do not. Not compared to you, all tall and imposing and...”

“Frisk. You look amazing, I promise. That dress is perfect on you. If it wasn’t so expensive, I’d be tempted to rip it off of you when we get home.” Asriel’s voice has husky, and very very close to Frisk’s ear. The human couldn’t help but whimper quietly, wishing that they could escape but also very glad they couldn’t.

“As it is, I’ll have to settle for simply taking it off. But that’s for later. isn’t it? We have a prom to attend first, which is starting any moment now.” Asriel stepped back, brushing himself down and offering a hand to Frisk, who nervously took it, their mind full of things to try and get rid of the arousal Asriel’s voice had triggered before it became visible.

The prom itself passed by mostly in a blur, Asriel and Frisk walking around, talking to people and occasionally being offered dances. The evening was pleasant, if very alien in a variety of ways, especially to Asriel who hadn’t even heard of this particular human custom until a fortnight or so ago.

Later in the evening, everybody gathered was silenced by Toriel, who was stood at the front of the great hall used for the prom, a spotlight on her as she stood in front of a microphone.

“Good evening, my students. I hope that the prom has been to everybody’s satisfaction. However, there is one last matter to attend to. That of this year’s Prom Monarchs.” Toriel’s voice was clear and Frisk couldn’t help but laugh quietly. Of course Toriel would find some way of making the title all-inclusive.

“Now, as you are all aware, everyone is this hall was asked to vote last week on who your Monarchs would be, and now is the time for the winners of said vote to be announced.” Frisk froze. They must have been ill on that day, they hadn’t voted. What if people had voted for them? Or not them but Asriel and someone else? Or not Asriel, but them and someone else?

Sensing Frisk’s panic, Asriel took their hand in his own, gently stroking the back of Frisk’s hand. “Relax, Frisk. It’s not like it’ll be us, so don’t look so nervous.”

Frisk nodded weakly. Of course it wouldn’t be them. Asriel was much more likely, but they decided not to say that. If Asriel won one of the titles then good for him. He was popular, had numerous titled roles in the school, and he was gorgeous to boot, so it wouldn’t really be a surprise to see him win.

“So, without further ado, could-” Frisk looked back toward Toriel, their breathing catching in their throat despite themselves. “Frisk and Asriel Dreemurr come to the stage?”

Oh shit. That was not at all what Frisk was prepared for. They didn’t know what exactly they had prepared for but it sure wasn’t that. They froze in place, feeling like they were dying a little inside as they saw almost everyone in the hall staring at them, the heat of Asriel’s hand the only comfort they had.

“Well, c’mon Frisk. It’s not going to do us any good standing here.” Asriel’s tone was soft, and hopefully as caring as he had meant it to sound. Frisk stayed rooted to the spot, however, so Asriel decided to save Frisk embarrassing themselves by being the one doing the embarrassing instead.

Asriel scooped Frisk up, bridal-style and carried them up toward the stage, only deepening Frisk’s silent wish that they had SAVEd before the prom so that they’d be able to escape this somehow. Barely able to stand from nerves, when Asriel put them down Frisk found themselves leaning heavily against their boyfriend, unable to look at the assembled crowd.

“Now, I know what all of you are thinking, but no I did not have any say in who won Prom Monarchy. This is purely on yourselves.” Toriel spoke loudly and clearly, internally very proud that her children had won what was effectively a glorified popularity contest.

Frisk’s thoughts were barely cohesive enough to register what was happening, their eyes glazed until Asriel was made to step aside from Frisk, snapping them back into reality. They looked toward their partner, swallowing hard as they tried to remember what actually happened after prom monarchs were crowned.

Their memory was refreshed the moment they saw Toriel placing a somewhat overly ornate crown atop Asriel’s head, where it rested snugly between his horns, and a sash made of what seemed to be silk was also put upon him, the white fabric very visible over his navy-blue suit.

Frisk realised that they were also about to be crowned, and stepped up to Toriel nervously, their hands shaking as they bowed their head slightly for the, thankfully less ornate, crown to be placed upon their head, as well as the sash that matched Asriel’s perfectly.

The next step from here would be the dance. They would have to dance with Asriel, beneath a spotlight, in front of everyone. Frisk had never felt more glad that Toriel had been very strict on them with their ballroom lessons.

“Now, if you all would not mind clearing a space, it is time for the Monarch’s Dance.” Toriel’s voice carried well even when she wasn’t stood directly in front of the microphone, and Frisk found some small comfort in Asriel’s heat as Frisk moved a little closer, sliding their hand into Asriel’s own.

Once enough space had been cleared, Asriel carefully led Frisk down into the center of the now-open space, a soft and reassuring smile on his face. “Don’t look so worried. We’ll be fine.”

Frisk nods weakly, placing their hands in position as Asriel did the same. This was fine, Frisk and Asriel had learnt how to dance together, and Frisk wasn’t inexperienced in dancing in dresses, either. They just had to focus on Asriel, nobody else. Ignore the crowd and focus on who was important.

The song was simple enough, a pleasant melody that was similar to what the pair were used to dancing to. Asriel led, as was the way they had always practiced, and the two began to dance.

Asriel was finding this much less worrying than Frisk seemed to be. He tightened his grip on his partner, smiling softly as they continued to dance, both too focused on the other to care about the crowd. Asriel felt completely at home here, moving in perfect tandem with Frisk as they danced together, although the caprine found himself wanting. Despite them being watched, the situation was undeniably romantic and Asriel was almost desperate to kiss Frisk. But that could wait until the end of the dance. He had to make it dramatic, after all, if only to embarrass Frisk more than it would already.

Much to both Frisk and Asriel’s relief, the dance only lasted a short time more. Frisk was much less relieved, however, when Asriel shifted his weight, pushing Frisk down and dipping them. Frisk almost slipped from Asriel’s grip, and in their panic they thew their arms around the caprine’s neck.

Frisk would have complained about the surprise, but the moment those thoughts registered in Frisk’s head, they were replaced with overwhelming embarrassment as Asriel kissed them, hard. Frisk tried to resist, but Asriel pulled away before they could do any such things.

“You’re a jerk. Don’t surprise me like that again.” Frisk whispered, leaning on Asriel to try and aid their dizziness as Asriel pulled them back upright.

“I love you too, Frisk.” Asriel says, laughing quietly as the pair walk away, passing through the crowd, with Asriel leading Frisk aside once they get to a quieter area, just outside of the hall. Once there, Asriel pushed Frisk up against a wall, pinning their wrists above their head.

“A-Asri, what are you doing?” Frisk whimpered, a hot rush of embarrassment springing to their cheeks as they looked up to Asriel, who seemed far less so.

“You didn’t seriously think I’d be satisifed with a kiss like that, did you? I couldn’t exactly make out with you in there. But out here, I can.” Asriel’s tone was almost predatory as he leant down, kissing Frisk’s neck. “And I will, too.”

Frisk hissed quietly, instinct forcing them to crane their neck for Asriel. “We could get seen, Asriel.” Their tone was sharp, but more out of worry than anything else. Frisk wasn’t exactly fond of showing affection in public, despite how happy they were to show it in more private situations, and they certainly didnt want to be seen with Asriel pinning them to a wall.

“I know we could, Frisk. But I can’t resist you any longer.” Asriel growled, kissing Frisk’s neck and biting gently, determined to bruise his lover’s neck. While he was focused heavily on Frisk during the dance they had just shared, he wasn’t ignorant of the stares that others were giving to them, especially to Frisk.

Asriel was a little worried that he felt so possessive, but Frisk was his partner, nobody elses. And if covering Frisk’s neck in lovebites made that obvious, then Asriel was more than happy to provide them, especially when risk seemed to enjoy it so much. The human was writhing in Asriel’s grip, their breathing heavy against the caprine’s fur.

“A-Asri, don’t. Not in public.” Frisk wanted to resist, but there was a worryingly large part of them that was enjoying this, both the public aspect and how forceful Asriel was being. Frisk’s willpower seemed to be incredibly weak when Asriel was involved, they found. Even more so now.

“Come on, Frisk. You’re into this.” Asriel growls, dragging his tongue over the now colored flesh on Frisk’s neck as he pushed himself closer to his younger sibling, holding him against the wall.

Frisk whimpers quietly, the harsh surface of the bricks scratching at their back, pulling at the skin. “You’re gonna be explaining all these wounds to Mom, you hear me?” There was so little feeling behind those words that Frisk felt embarrassed for it.

“I’ll explain whatever I have to, Frisk. You’re mine, after all.” Asriel tightened his grip on Frisk’s wrists, using his free hand to grab their leg, bringing it up against his own. “So many people were staring at you, that I’m going to have to prove it to them.”

Frisk hissed quietly as their back was scratched open, glaring daggers at Asriel. “They were jealous of me, idiot. I have the most attractive date there.” Despite their protests, Frisk didn’t resist as their leg was pulled up.

Asriel grinned slightly, pulling Frisk closer. “Jealousy or not, I’m not gonna stop. You’re enjoying this far too much.” A small pang of guilt tugged at Asriel as he realised this could easily go too far. But Frisk was enjoying this and so was he. Perhaps too much, given the sudden tightness in his pants.

“It’s such a shame that we’re in public. If we were at home, I’d pull this dress off you and really show you how much I love you.” Asriel growled into Frisk’s ear, grinding up against his smaller partner. It was some small aid to the aching need in his groin, but no aid at all for the lust he had no way to remove.

Frisk could barely even summon the words to protest, the pain in their back reduced to a dull ache at this point. “Stop. As-Asri, stop. Please.” Not that Frisk wanted Asriel to stop, they wanted him desperately to continue. But there was no more that the pair could do without breaking some laws, and Frisk did not want this evening to end in prison.

Asriel stopped, keeping Frisk close as his hot, needy breath flowed over Frisk’s neck. “What’s the matter? Have I hurt you?” The dominant tones vanished from Asriel’s voice, replaced immediately with concern.

“No. I mean, my back hurts but no. A-Asri, let’s go home.” Frisk’s voice was barely above a whisper, a hot blush severe enough to make them dizzy coursing through them. “Together. So you can do those things you said.”

Asriel laughed softly, before releasing Frisk and stepping back, brushing down his suit. “And here was me thinking I’d always be the one to ask, Frisk.” He extends a hand, which Frisk takes as the pair begin to walk back towards their home. “I’ll text Mom later, before you worry about that.”

Frisk nodded weakly, barely able to focus for the rest of the thankfully relatively short journey back to their home. Nerves and insecurity was too busy filling the human’s mind, the stupor they caused only broken when Asriel stepped away from them to open the door.

“You know you’re cute when you’re nervous, right Frisk?” Asriel teases, pushing the door open and stepping inside, glad that Frisk was following close behind. He locked the door behind them, before deciding to repeat what he had at school, grabbing Frisk and pushing them into a wall.

“A-Asriel! We just got home, w-whats gotten into you?” Frisk struggled against their brother’s grip, nervous anticipation shown on their expression. “Don’t you at least want to wait until we get into the bedroom?”

Asriel growls quietly, biting at Frisk’s neck a few times. “No, I don’t. I’ve waited the whole walk home, and much longer besides. I want to make you feel good.” Asriel’s voice so close to Frisk’s ear causes a shiver to crawl down the human’s spine, a shaky and slow breath escaping them.

“Alright. Alright, okay.” Frisk’s voice cracks slightly and they curse internally, any hope of focusing destroyed as Asriel’s free hand works its way around to the zip of the dress, pulling it down and allowing the garment to drop, leaving Frisk exposed bar the underwear that looked rather painfully tented.

“Dear me, Frisk. You almost sound like you’re in pain. I’m sure I can help you out, little brother.” Asriel laughs softly, his free hand moved and slowly stroking Frisk through their underwear, causing a quiet, clearly held back moan to escape the younger of the two.

“D-don’t call me your brother, Asri. Not before we’re gonna have sex.” Frisk looked up toward the ceiling, their neck craned to allow Asriel to bruise it further.

“But you’re so adorable when you’re flustered that I may just have to.” Asriel teases, moving his hand away from Frisk’s crotch as he pins Frisk harder against the wall, one of Frisk’s wrists held by one of his hands.

Frisk struggles slightly, the effect ruined somewhat by the clear and intense arousal coursing through the human’s body. “Don’t be a jerk, Asri. Please.”

Asriel laughs quietly, stepping toward Frisk and pushing his crotch up against Frisk’s, growling quietly. “I’ll be anything you want me to be, Frisk. But right now, I’m going to be a jerk, because I want to.” With a smile, Asriel steps back from Frisk, winking and walking through to the living room, completely aware that Frisk would follow him. Frisk would eat from the palm of his hand if he asked, when they were like this.

Frisk decided not to answer, following their partner after picking the dress up from the floor, hanging it over the door to the living room before pushing it as closed as it would get. Asriel was sat upon the couch, waiting for them. 

“Come on Frisk, don’t keep me waiting.” Asriel chides, pulling Frisk on top of him as soon as they got close enough. With Frisk now straddling him as he desired, Asriel smiled greedily, entangling a hand in Frisk’s hair and kissing them hungrily, forcing their mouth open and pushing his tongue inside.

Frisk leant into Asriel, nearly delirious from their oxygen suddenly being cut off. Struggling futilely against their larger sibling, Frisk unintentionally shifted their weight directly onto Asriel’s crotch, a sudden rising pressure pushing up against them. Frisk would have laughed from embarrassment if they weren’t too busy being asphyxiated by Asriel.

Asriel himself simply closed his eyes in pleasure, Frisk’s weight on him causing arousal in ways he didnt realise he could get as he pushed his tongue deeper into Frisk’s mouth, holding them close as he did so. It was only when Frisk started to feel limp against him that Asriel finally pulled away, leaving Frisk gasping and struggling for air as they leant against him.

“Lightheaded. Don’t...don’t do that without telling me.” Frisk whispered, the room spinning around them as they leant against Asriel, resting their head on his shoulder. “Permission is needed.”

“Got it. You enjoyed it though, didn’t you Frisk?” Asriel’s voice carries a quiet, deep growl as he moves his hands down to Frisk’s hips, holding them in place on his achingly needy erection that was tenting his suit pants. “You’re acting innocent but deep down you love it.”

Frisk swallowed hard, too nervous to raise their voice above a whisper despite there being nobody around but Asriel to hear. “Maybe I do. A little.” They lean back, looking into Asriel’s eyes, the dark sclera as deep as always as Frisk stares into them. “Not everyone is as innocent as they look.”

Asriel laughs softly, hooking his thumbs in the band of Frisk’s underwear. “You must be hiding some secrets then, Frisk, to say that. Some dirty dreams about me, perhaps?” The badly hidden embarrassment and shock that spreads over Frisk’s expression tells Asriel all he needs to know. “Why not tell me about them?”

Frisk shook their head, impatiently shifting in Asriel’s lap. “I don’t want to keep talking. You told me you’d prove how much you loved me, Asri. Can we get to that already?”

Asriel smiles slightly, leaning forward and kissing Frisk on the forehead. “Only if you ask me properly. What do you want me to do to you, Frisk?” Asriel felt slightly cruel drawing it out like this with an obvious question. But a significant part of him was getting a dark sort of joy from teasing Frisk like this.

Frisk choked on their words, gripping viciously at the shoulders of Asriel’s shirt. “Asri, don’t. Don’t make me say it.”

“I want to hear it, Frisk. Please.” Asriel leant in, gently kissing Frisk’s forehead. “Just this once.”

Frisk swallowed, before nodding. “Once. Only once.” They took a moment to collect themselves, before exhaling slowly and looking back to Asriel. “A-Asri, I want..I w-want-” They choke up, hissing in frustration. “I can’t. I can’t say it.”

Asriel nods, hugging Frisk close to his chest. “Alright. Thank you for trying Frisk, and I don’t mind doing most of the talking.” Frisk offers a quiet noise of agreement into his fur, and Asriel leans into them, gently biting into their ear. “Nor do I mind fucking you, Frisk.”

Despite himself, Asriel almost laughed at the quiet, ashamed whimper that came from Frisk as a response to what he said. “But first we should get rid of clothes, shouldn’t we?” Asriel doesn’t wait for an answer, instead starting to shed his shirt and wriggle out of it, pushing it aside.

“Asri, is this okay?” Frisk asks quietly, nerves turning into panic as their heart starts to race for the wrong reasons. “I mean, is this really okay?” Their grip shifts from Asriel’s missing shirt to their arms, shivering from worry.

“Of course it’s okay, Frisk. I want to do this, and you said you do too.” Asriel tried his best to be reassuring, taking Frisk’s hands in his own. “We’ll take it slow. Mom and Dad won’t be back for hours.”

Frisk nodded, gently rubbing the palms of Asriel’s hands. “Okay. I love you, Asri.” Still barely louder than a whisper, Asriel barely hears Frisk but smiles regardless, shifting his weight beneath the human almost to remind them that he was in fact, still very much aroused.

Frisk yelps quietly, the shift in pressure causing a spike of heat to hit their crotch. “That felt big. Asri, h-how big are you? I-I mean, if it’s going to g-go in me, I’d need to, uhm..yeah.” Frisk felt like curling up and dying from embarrassment, much to Asriel’s discomfort. Teasing was one thing but seeing Frisk worry so much wasn’t good.

“I’ve never measured it. But I’m pretty big. That’s one of the reasons we’ll be going slow.” Asriel says, trying to keep his tone calm. “Could you get up a little, I want to unzip my pants.”

Frisk nods quickly, pushing themselves up to allow Asriel to slide his hands between the two, the sound of his fly unzipping deafening in the otherwise silent house. Once Asriel had moved his hands away, he put them gently on Frisk’s shoulders, pushing them down onto his erection again, this time with nothing more than underwear seperating the two.

Frisk mewled quietly, the much more noticeable heat from Asriel’s erection causing their own arousal to become visible through their own underwear. “How are you so calm?”

Asriel shrugs, one hand moving to Frisk’s hair and the other to Frisk’s crotch, gently feeling him through the underwear. Frisk shifted and stuggled to keep themselves quiet as he did so, but the caprine was relieved to see that his younger sibling seemed to be slowly easing into this situation. “One of us needs to be. So, what do you want to do?”

Frisk pales, stumbling on their words. “Me? Bu-but you said you were in charge.”

“I know, Frisk. But we both need to decide together.” Asriel reassured Frisk, taking the initiative slightly and slowly rocking his hips, grinding himself up against Frisk.

“C-crap. I want...can I touch it?” Frisk asked nervously, their whole body still shaking from nerves and the cold that they were just now able to realise was a lot more intense than they expected.

“Of course you can, Frisk.” Asriel shifts, letting go of Frisk and throwing his arms over the back o the couch, a small expectant smile on his face. Frisk nodded, the spark of Determination forming within them as they climbed down off of their brother, grabbing the waistband of Asriel’s underwear and pulling it down, allowing Asriel’s erection to come free.

As much as they didn’t want to, Frisk couldn’t help but whimper quietly at the sight of it. Frisk had always thought they were decently well-endowed at around six inches, but Asriel looked at first glance to be around nine inches, and far, far thicker than Frisk was. The first set of thoughts that came to their mind was how difficult and painful it would be to try and take something like this into them, even with lube.

Swallowing hard, Frisk reached out, gently wrapping their slender fingers around Asriel’s length, looking up to the caprine for guidance. Unlike Asriel had been with him, Frisk was terrified of making some sort of mistake when touching his lover.

“It’s alright, Frisk. Just do what you do with yourself.” Asriel says quietly, reaching down and smoothing Frisk’s hair, causing them to blush. “You’re doing great.”

“T-thanks, Asri.” Frisk says, finally gaining enough courage to speak at a more sensible volume. Gripping Asriel at what they hoped was the right pressure, Frisk slowly began to stroke him, embarrassed at how intense the happiness that burned in their chest was as the motions caused a deep, lustful growl to come free from Asriel’s maw. Frisk tried desperately to ignore how their erection twitched at the growl, and made extra sure to never tell Asriel he had just discovered how arousing growling was.

“That’s the spot, Frisk. R-right there.” Asriel grunts, hissing through his teeth as Frisk continues the slightly too-careful rhythmic motions. The feeling of human skin up against him instead of the thicker, furred skin of his own hands was an intense set of sensations in its own right, but that hand belonging to Frisk only made it all the more severe.

Satisified with how well it seemed to be going, Frisk decided to take it a little further, tightening their grip on Asriel as well as speeding it up, swallowing and focusing on what they were doing instead of the intrusive thoughts telling them to just open their mouth and taste him. Asriel had done so for them, yes, but they weren’t ready for that just yet.

“S-shit, Frisk.” Asriel moans, his tongue dropping free from his maw, drips of gray-black drool clinging to his chest fur. Frisk blushes at the sight. They’d never seen Asriel so blissful, and Frisk felt almost as happy as Asriel simply from knowing that it was them that caused it.

Frisk continued as they are for a few minutes more, almost falling into a trancelike state as they observe Asriel listlessly shifting and writhing, occasionally pushing his hips up against Frisk’s hand. So, hearing Asriel speak up startled them, causing them to accidently squeeze harder than they would have liked on Asriel’s erection.

“Ow, jeez. I only asked if you wanted to do more, you didn’t have to crush me like that.” Asriel teased, causing Frisk to apologise profusely. “Hey, relax. C’mon, climb up on my lap again.”

Frisk nodded, their eyes glazed as they do as commanded, straddling Asriel and pushing their weight up against him. “I love you, Asriel. Thank you for putting up with my nervousness.” Their speech was more monotonous than normal, with them having fallen into a near-trance as some form of defence from the panic burning in their chest.

“Hey, Frisk? Frisk, are you okay?” Asriel waves his hand in front of Frisk’s face, causing them to startle and shake their head, the focus coming back to their eyes. “Listen, Frisk, we can stop. You seem really not okay with this.”

Frisk shakes their head, smiling softly. “I’m just really nervous, Asri. The most intimate contact I’ve ever had has been exclusively with you.” They laugh quietly, scratching the back of their neck nervously. “I don’t really know what to do, I guess.”

Asriel smiles warmly, resting his forehead against Frisk’s. “I have no idea either. So why don’t we just figure it out?” Asriel slowly moved his hands down to Frisk’s lower back. “Like I said, Mom and Dad won’t be back for hours. We have time.”

Frisk nods weakly, a faint red tint to most of their skin from embarrassment as they rest themselves against Asriel, counting each breath as it comes to keep them regular. “You’re still okay with leading aren’t you?”

“Of course, Frisk.” Asriel says quietly, holding Frisk’s rear. “I’ll help you through this as best I can.”

Frisk nods, biting into their lip as Asriel’s hands roam, a couple of his furred fingers grazing up against their entrance, causing a soft, throaty moan to escape them. Asriel winked, pushing his fingers closer and gently trailing a claw near to Frisk’s most senstive area, causing the young human to curse into Asriel’s fur, where they’d buried their face to hide.

“You liked that more than I thought.” Asriel teases, before pulling his hand away, bringing it up to his chest. “Y’know, if my fingers were wet, I could do more than tease you.”

Frisk slowly pushed themselves away from Asriel’s chest, looking up to the caprine before nodding weakly, opening their mouth and gently sucking on Asriel’s fingers to lubricate them. They tried not too enjoy it too much but found themselves struggling with some sort of pleasure high, their head fuzzy as they leant into Asriel’s hand, surprised to find that they even enjoyed how he tasted, slightly.

“Chill, Frisk. I said make them wet not try to lick them to the bone.” Asriel jokes, gently pulling his now-soaked fingers from Frisk’s mouth and placing them back where they were, scratching his claws at Frisk’s rear, causing them to hiss.

“T-that hurts, Asri.” Frisk complains quietly, leaning back against their partner. “A-and I thought you were going to try and put...yknow.”

Asriel nods slightly, pulling Frisk’s chin up and kissing them passionately, using the distraction to push one of his fingers into Frisk, his other hand gripping the back of Frisk’s neck to hold them in place, minimising any resistance that the human would give.

Frisk writhed and cursed against Asriel, biting at his lips and neck, desperate to get him back for the aching, stretching pain they were receiving. Feeling Asriel’s finger inside them, shifting and curling, made Frisk desperate for more. “F-fuck, Asri. That feels so good.”

Asriel smiles, biting and kissing at Frisk’s neck, carefully and deliberately starting to push his finger into Frisk, starting a slow rhythm as the pair aggessively bit and kissed and sucked at each other’s necks, Frisk weakly grindng his hips up against Asriel as they did so.

“You think you’re ready for more, Frisky?” Asriel growls in the human’s ear, a dark glee surging through him when he sees Frisk shiver from his voice. “Let’s see if we can take a second finger shall we?”

Frisk nods, panting and drooling onto Asriel as they grind their hips on Asriel’s own, biting down viciously into the caprine’s neck as they feel a second digit worm its way into them, forcing them wider than they can ever remember being. Frisk had experimented before to see what this felt like when they were getting off, but with Asriel’s hand it was something else entirely.

“You’re very receptive to this, huh Frisk? It’s like your body is reminding you that you want to get fucked by me.” Asriel whispers into his lover’s ear, rhythmically assualting Frisk’s insides with short, sharp thrusting motions. “That’s what we’re stretching you out for, after all.”

Frisk nods weakly, swallowing repeatedly to avoid drooling too heavily. “Asri, I’m so hard. I want to feel you up against me. Not in me yet, just...grind with me. Please. Please, Asri.”

Asriel was surprised to hear the normally oh-so-innocent Frisk begging for sexual release. He needed his own, however, and was more than willing to comply. So Asriel lined the pair up, before holding Frisk down with his free hand, as he started thrusting against the small human, a harsh friction on the pair as they started grinding against each other, the heady smell of their combined arousal permeating the room.

At this point, Frisk gave up on trying to pretend that they were innocent. They were far too high on pleasure and sexual frustration to keep up that charade. So they decided instead to speak their mind.

“Asri. A-Asri, please. I want you to fuck me.” They purred, grinding up against Asriel, barely even registering the pain-turned-pleasure inside of them. “Fuck me, big brother. Right here, on the couch. Or upstairs on our bed. Just please fuck me.”

Asriel smiles against Frisk’s neck, letting out a slow and hot breath against the exposed, sweaty flesh. “Gladly, Frisk. Upstairs seems better, considering that’s where the lube is. I don’t want to hurt you. Unintentionally.” He bites into Frisk’s neck briefly, before pulling his fingers free from Frisk, causing the human to gasp quietly, shakily getting to their feet as they put their undewear back on properly, before helping pull Asriel to his feet.

“Now, let’s go. I can hardly waste time when you’re this turned on, can I?” Asriel teases, scooping Frisk into his arms and carrying his younger sibling up the stairs, kicking the bedroom door closed behind them and, after placing Frisk on the bed, went to lock it.

“Now we can’t be interrupted. Unless Dad accidently uses a shortcut into here.” Asriel quips, walking back over toward the bed and shedding the remainder of his clothing on the way there, showing Frisk his full self as he opened the bedside table that they shared, taking a small bottle of lube that he’d picked up for when this would happen, a mixture of concern and barely-contained lust clear on his expression.

“You talk too much, Asri.” Frisk whines, shifting and trying desperately not to pleasure themselves, wanting that to be Asriel’s work. “Please don’t take so long when we’re actually having sex.”

Asriel laughs softly, climbing onto the bed and kneeling between Frisk’s legs, pushing them apart before opening the bottle and smearing some of the semi-clear fluid within onto his fingers, the same ones that had been inside Frisk mere moments before. “First you stop acting innocent, now you’re learning sarcasm? Golly Frisk, when you’re horny you’re a completely different person.”

“Shut up and get into me already, will you? What if Mom and Dad come home?!” Frisk leans up, bristling with frustration and an aching impatience. “It’s really hard to enjoy this when you’re taking so long Asri.”

Asriel sighs, shaking his head as he pushes Frisk onto their back, holding them down as he pushes his fingers against Frisk again. Frisk tries to buck against him, but the caprine holds firm, bending down to kiss Frisk on the forehead. “I get it, Frisk. Let me make you feel good, okay?”

Frisk nods weakly, relaxing as best they can before screwing their eyes shut as Asriel’s fingers slide into him, aided by the lubricant. The cold, slick coating on Asriel’s fingers felt completely different from how his fingers felt without it, but it wasnt entirely unpleasant.

They couldn’t say the same when Asriel started shifting his fingers, spreading them inside them. That felt significantly less pleasant, instead leaving hot surges of pain through their lower half. They cried out quietly, writhing beneath Asriel’s grip. “Ow! Did you have to do that?”

“Yes, I did. I’m not bragging when I’m saying that I’m pretty well-endowed. I want this to hurt as little as possible.” Asriel reassures Frisk, easing up very slightly as he scissors his fingers inside of them, feeling them tighten and twitch around him only enhancing Asriel’s own arousal, not that Frisk wasn’t visibly incredibly aroused themselves.

The pair continue like this for a couple of minutes longer, Asriel offering constant reassurance as Frisk arched and writhed, a string of hoarse curses coming from them all the while. “Come on, Asriel, isn’t this done yet? You’ve been stretching me forever, and I can’t get to myself like this.”

“You’re ready to move on? And here was me thinking you were enjoying it.” Asriel laughs softly, but does as Frisk wishes anyway, slowly drawing his fingers free and kneeling up between Frisk’s legs again. “I think you should be properly lubricated, but I could always make extra-sure.”

“Hm?” Frisk raised an eyebrow, confused as they pushed themselves up on their elbows, more than a little shocked to see Asriel crawling back, nuzzling against Frisk’s thigh. “Asri, what are you doing?”

Asriel looks up to Frisk, winking as he does so. “Well, Frisk, I don’t want to try and penetrate you while you aren’t lubricated enough. And I can provide more than enough.”

Frisk paled as Asriel punctuated the end of his sentence by letting his long, prehensile tongue hang free from his maw, dripping his thick gray drool onto the bedsheets. “What? Asri, don’t be stupid. I can’t have that inside me. Having the other big, sticky thing inside me is gonna be hard enough.”

Asriel shrugged, bringing his tongue back before smiling and baring his fangs, climbing over Frisk so their faces were almost touching, Asriel’s legs keeping Frisk’s held apart. “Maybe another time then. For now, we should get to the best part.”

“Jeez, when did you learn to be so smooth? You’re supposed to be a dork.” Frisk complained, wincing a little as the comment earns them a short, sharp bite to the neck. That was likely to end up amongst the two dozen bruises Frisk knew they’d end up with soon enough.

“I’m your dork, Frisk.” Asriel laughs softly, trading bites for kisses as he shifts and lines himself up with Frisk, grinding slowly against them and marvelling at how the normally expressionless Frisk would squirm and show such intense emotion when they were doing things like this.

“You aren’t going to be my dork for long if you don’t hurry up!” Frisk half-whispers, glaring exhaustedly at their partner. “You’re enjoying teasing me too much.”

Asriel nods, grinding harder against Frisk and gasping quietly as he feels the first trails of Frisk’s precum dripping out of them, the sticky fluid clinging to both of their erections. “Well, even if I wanted to tease you more, I don’t want you to cum before I’ve even gotten inside you.”

Frisk panted quietly, grasping at the bedsheets. Only able to utter the word “finally”, the human shifted and struggled to push themselves up on their elbows as Asriel knelt up, taking Frisk’s hips in his hands.

Asriel smiled softly to his lover, holding them in such a way that he was lined up with Frisk’s now-lubricated ass. “Are you sure you’re ready for this, Frisk? This is your last chance to back out.”

Frisk shakes their head rapidly, grunting quietly when doing so causes the room to spin around them. “No backing out, Asri. I want you to be my first, and want that to be now.” Despite how admant they sounded, Frisk’s heart was pounding from nerves. A first time like this could only happen once after all.

Asriel nodded, a serious look on his face. “Alright, Frisk.” His serious glower changed into a small, loving smile as he leant into Frisk slowly, a sharp gasp escaping him to accompany the more hoarse, desperate one from Frisk.

Frisk felt nearly completely overwhelmed already, and things had literally only just begun. Asriel’s fingers had been sizable, but Frisk had been so distracted that the pain was numbed, the sensations simple to cope with. This was entirely different, from the heat to the shape to how it didn’t hurt at all like Frisk had expected.

Not that it was painless, but the pain was of a different nature to that which the human was expecting. Swallowing hard, Frisk gasped and looked to Asriel who already looked concerned that he’d done something wrong, staying motionless even though he had barely entered. “I’m alright. Just adjusting. You can move.”

Asriel felt unsure, but Frisk’s tone was genuine. The caprine shifted, tightening his grip on Frisk and finding a worrying amount of pleasure as his claws pierced the skin, causing a desperate moan to come from the small human. Pulling Frisk slowly as he leant into them, Asriel couldn’t hold in his own sounds of pleasure, his long black tongue dropping free of his maw.

Frisk barely felt capable of holding themselves up on their elbows, but the sight of Asriel’s tongue and how much he seemed to be enjoying this was filling them with too much Determination to let them drop down to the mattress. Frisk was entirely unable to judge how much of their brother was inside them now, but the pain was increasing along with a significantly more powerful wave of pleasure. 

Filled with Determination and desperation in equal measure, Frisk was barely aware that they had lifted their legs and wrapped them around Asriel’s waist, as if assuming the caprine would try and escape. “A-Asri...”

Asriel smiled, leaning forward and dropping down over Frisk, his hands splayed either side of the human as he kissed them hard, forcing his tongue into their mouth as he closed his eyes, slowly pushing himself deeper into Frisk, who by now was completely caked in sweat and was visibly tense all over.

Frisk threw their arms around Asriel’s neck, more than grateful for the distraction from what little pain still burned within them. Unlike before, when Asriel had been forceful but still careful and gentle; this time his tongue was completely dominating, holding Frisk’s at bay as part of the caprine’s thick, prehensile tongue forced into the human’s throat, causing a bulge to it.

Asriel found himself running entirely on autopilot, so overcome with desire that he almost began to worry whether or not this would spark his Hyperdeath form. Feeling Frisk against him, however, writhing and gasping as he pushed his tongue into their throat, subdued those worries as he simply drank in all the sensations that Frisk was granting with their entire body.

Frisk’s grip became limp, spots of color starting to form in their closed eyes as Asriel toyed with the inside of their throat, breathing becoming increasingly difficult. Entirely unable to resist, Frisk dropped their arms from Asriel’s neck, falling free of the kiss as they gasp for air, a sharp rush of agony spearing into their lower half as Asriel pushes particularly clumsily into them.

“Don’t you want to kiss me, Frisk? Taste my tongue while I fuck you?” Asriel teased, licking at the bruises forming on their neck. He knew Frisk didn’t like being teased, or like him talking when this was happening, but he found it far too fun to resist. Especially when Frisk’s movements to glare at him caused their insides to tense and grip him in different ways, triggering the caprine’s own desperately needy erection to start creating precum.

Any witty retort Frisk had was drawn out from their mind as they felt Asriel’s fluids clinging to their insides. Frisk’s hands grasped for the bedsheets, desperate for something to hold onto, as they began to realise that there could be a big problem with what would inevitably happen.

Frisk had never, for obvious reasons, seen or heard about how much sexual fluid monsters made. But judging by the sheer amount of stickiness they could feel within them, Frisk began to panic that it would be too much to not completely ruin Frisk’s insides, or the bedsheets, or wherever it ended up.

“F-Frisk. Frisk, I’m going to push in further, alright? This is probably really gonna hurt.” Asriel half-whispers, half-gasps as he thrusts into Frisk, taking care not to go too far in. He didn’t want to injure Frisk after all. Not without permission first, if Frisk was into that, even.

Trying not to get distracted by the new thoughts of a bound, begging Frisk out of his mind, Asriel gently trailed kisses up his lover’s neck, a little too proud of how many different colors were there.

Frisk, to their intense annoyance, lacked the muscle strength to even move to half-heartedly swipe at Asriel for the surges of pain that had wracked Frisk when he had pushed deeper. Frisk knew that Asriel was far from completely inside them, but didn’t believe that their body could take anymore. “Asri. Don’t go further in, okay? This is a lot already.”

Asriel nods, trailing kisses up Frisk’s chin before planting a less gentle one on their lips, bringing a hand to Frisk’s head, tangling his fingers in their hair. Frisk responds in kind, reaching for Asriel’s neck as they kiss back with as much force as he had, their arousal causing them to drip their own precum onto their stomach, their cock twitching as they fond themselves already close to orgasm.

Asriel, less close to that point than Frisk, decided that he needed to get that bit further and catch up to them. Pulling his hips back, Asriel draws a quiet hiss from Frisk between kisses, before pushing back in again and feeling them open their mouths in a gasp. Taking full advantage, Asriel began a careful, rhythmic thrusting into Frisk, all the while toying with their tongue as he pushed his own into their mouth, and throat as before.

Frisk found themselves in a twisted form of heaven, formed from pains they never expected to feel. Their older brother-turned-lover had them pinned down and was sharing in their first time and Frisk’s own deflowering; and on top of that the caprine was currently, for lack of a better term, also fucking their throat with his disturbingly agile tongue. They hadn’t expected any of these things to be pleasurable, let alone so pleasurable that it had almost brought them to climax already. 

Asriel smiled against Frisk, pulling away suddenly and pulling on their hair, exposing a noticably unmarked part of their neck before sinking his fangs into it, more viciously than he had before. A growing part of Asriel was feeling intensely possessive of Frisk, much as it had when they had danced together an hour or so prior, when they were being stared at by the other patrons of the prom.

But now, Frisk belonged completely to him, both romantically and sexually. They were siblings, partners and now lovers. The caprine smiled as Frisk cried out loudly at the pain he must have caused with this bite, grinding his fangs into their neck as he continued his careful movements inside them, more of his precum soaking the pair as he did so.

But he still needed proof. Not for himself, he knew that Frisk was his, but for others. Anyone who would look at Frisk while the pair were out would know exactly what Frisk was to him and that alone made him almost as happy as the fact that Frisk trusted and loved him enough to let him be their first time.

“S-shit, Asri. Asri, please. You’ll make me bleed, a-and I’m so fucking close.” Frisk gasps, grabbing Asriel’s horns and gripping them tightly. After teetering on the edge of overwhelmed for most of this, Frisk had finally tipped over, barely able to focus on how many different kinds of pleasure were coursing through them. Between Asriel’s bites and his thrusting, Frisk’s mind was entirely blank of anything but the Determination to hold their orgasm at bay so that Asriel could cum before them, or at least at the same time.

A little surprised that Frisk had taken hold of his horns, Asriel pulled himself free of Frisk’s neck. Taking a guess that Frisk’s twitchiness and the spasming of the muscles that were gripping him so tightly inside them were showing how close Frisk was to orgasm, Asriel wanted to push them over the edge.

“F-Frisk. Frisk, I want you to cum. Prove to me that I’m making you feel good. Let me see it, let me see that pleasure covering your stomach.” Asriel’s tone was hoarse and growling, just as he knew Frisk enjoyed most. Hearing them gasping and feeling them shift and writhe underneath him only futher demonstrating that fact.

“I can’t. Asri, I can’t before you do.” Frisk feebly attempts to resist, despite now feeling so desperate for orgasm that they’d started pushing their hips against Asriel. A large part of Frisk hated that they were so submissive to that voice that Asriel could do. With that voice, he could demand them to do anything and they felt like they would.

Vivid images of the kind of thing Frisk was fervently trying to deny they wanted Asriel to command them to do flooded Frisk’s mind with that train of thought, causing them to cry out, their voice dripping with lust as they arch their back, their stomach pushing against Asriel.

Climax hit the human like a truck, their mind going completely white as their vision blurs and the aching heat of lust was finally expelled from them as they came, a half-dozen ropes of semen falling onto them as they pant and moan quietly, their chest heaving with each struggling breath.

“Doesn’t that feel better, Frisk?” Asriel asks, keeping the commanding tone to his voice, his heart jumping when he saw Frisk actually nod in reply. Perhaps there was a little more power in this particular tone of voice than he had initially realised.

“But you haven’t cum yet, Asri.” Frisk whimpers, wishing the world would stop drifting in and out of focus. “I want you to cum as well.”

Pushing himself up, Asriel looked into Frisk’s eyes. “I’m going to, Frisk. But where? Since I didn’t put a condom on, do you want me to pull out?” The forceful, commanding tone Asriel had was replaced now with a curious and concerned one. Asriel knew he was significantly more productive than Frisk was, and was rather worried that if Frisk wanted his seed inside them, that it wouldn’t cause any problems.

“Pull out? But, uh, then you’d cum on me. And I’d...be sticky, and c-covered, and-” Frisk stops, swallowing hard and blushing as if the thought of Asriel’s seed on them was the most sinful thing about this entire experience.

“That sounds to me like you want that, Frisk.” Asriel teased, feeling a familiar coil of heat and tension burning within him, his own orgasm not far away. The embarrassed glare Frisk gave him was all the confirmation he needed, and after a few more thrusts, the caprine pulled himself back, fully free of Frisk’s insides before taking his throbbing, soaked erection in his hand, his tight grip and rough, deliberate pumping more than enough to bring Asriel’s own orgasm to fruition, rope after rope of thick, dark gray cum hitting Frisk’s stomach and chest.

Frisk was almost in awe of how much Asriel was capable of producing, their hazy mind counting over a dozen ropes of semen hitting them before he finally stopped, leaving Frisk’s stomach, chest and even their neck covered in the stuff.

Their bedroom was permeated with the smells of sweat and sex, but neither Frisk nor Asriel cared. The events that just occurred were a huge step for them both in numerous ways, and their shared love was more intense than it had ever been before.

“Frisk...thank you. That felt amazing. And...thanks for letting me be your first. And for being my first.” Asriel spoke between pants, drooling a little as he pushed himself up onto his knees. Frisk gasped quietly at hearing the full sentence, blushing more than Asriel thought even the most embarrassed of humans could.

“Asri, you never said...I thought...” Frisk’s mind was too addled to finish the sentence, so instead they pushed themselves up with what little strength they still had, wrapping their arms around Asriel’s chest and hugging him tightly. “I enjoyed it too.”

Asriel grunted quietly as Frisk’s vice-like grip wrapped around his chest, but quickly returned the embrace. “Although, now that we’re both covered in gross stuff, shouldn’t we clean off? And maybe use an air freshener so its not quite so obvious we had sex?”

“Asri. Do you really think Mom and Dad would think we had done anything else, after coming home by ourselves, after our prom dance, and with all these huge bruises that are probably all over my neck by now?”

Asriel can’t help but laugh quietly. “That’s a good point. But it still smells really gross in here, and we’re really sticky and nasty.”

Frisk can’t argue with that, so they let go of Asriel’s chest and unstuck themselves from his fur, shakily holding themselves up as Asriel climbs off of them and the bed, offering a hand to help Frisk up. They take it, leaning against Asriel as the pair walk through to the bathroom. “Hey, Asri?”

“Yes, Frisk?” Asriel turns to look at Frisk, who looked every bit as wonderful in afterglow as they had throughout the entire experience. Asriel turned the hot water on, steam filling the room as the water cascaded into the monster-sized bathtub, which was plenty large enough for the pair of them.

“You know Mom is going to kill you for bruising me like this right?” Frisk jokes, sitting on the side of the tub, yelping quietly at the cold. “Okay. That was cold.”

Asriel laughed quietly, leaning back against the wall. “I’m sure she will, Frisk. But I’ll just bring up the time she forgot to take that collar with the nametag off in the morning, and then she won’t be able to judge me.”

Frisk covered their mouth, laughing quietly. “That was really weird. I never thought Mom would be into that too.”

“Too?” Asriel questions, a smirk on his face. “Was that a secret you just gave away there, Frisk? Do you like being collared?”

Frisk pauses, before turning to glare at Asriel. “Tell anyone and I will end you, Asriel.” Their tone is much less threatening than they hoped, and any intimidation they had hoped for was shattered when Asriel started to laugh.

“Don’t worry Frisk. Your secret is safe with me. And who knows, maybe someday you’ll get your own collar.” Asriel teases, climbing into the bath once enough water has filled it. Frisk climbs in a few moments later, their back against Asriel’s stomach.

“I hate you so much.” Frisk pouts, blushing intensely.

“Yes, I’m sure you do, Frisk.” Asriel smiles, ruffling Frisk’s hair and lying back, his head resting against the wall.

Frisk sighs, smiling happily before lying back as well, a heavy drowsiness overcoming them as the exhaustion from the afterglow finally kicks in. “You don’t mind if I fall asleep on you, do you?”

“Go right ahead, Mom doesnt mind us sleeping in the bath.” Asriel replies, gently playing with Frisk’s hair. “I’m kinda tired too.”

 

A few hours later, Toriel walks into the bathroom. A smile curls at her lips at seeing her children blissfully asleep in the bath together, much as they would nap there when they were younger. The bruises on Frisk’s neck and the gray tinting to their skin, however, quickly made that smile disappear. Asriel would have some explaining to do when he woke up.


	4. Consequences

**Notes for the Chapter:**

> Hey, Aithe here. So, I guess this is going to be a continuous fic now. I only planned this out to be a oneshot, but between how much I enjoy writing this and how much everyone seems to like it, I don't see any reason to stop just yet.
> 
> I realise that my non-smut chapters are quite a bit shorter than the smut chapters, but I find it a little harder to write these, I guess? I'm still new to writing this kind of thing after all, so I hope it's not a problem. Either way, I'd like to hear what you guys think about what goes on in this chapter. You guys seem to like the smutty chapters, so hopefully you like this one just as much.
> 
> Hope you enjoy!

Asriel cowered slightly, bowing his head. “I said I was sorry, Mom.”

Toriel placed her hands on her hips, her best withering glare pointed directly at her eldest child. “Sorry isn’t good enough, Asriel. You cannot just do those kind of things to Frisk without adequate preparation and protection. It could have brought serious harm to them, and you know that.”

Frisk spoke up quietly, feeling far more nervous than Asriel looked. Toriel had thus far ignored the human, focusing her tirade on the elder sibling, but Frisk felt that unfair. “Mom. Mom, it’s not Asriel’s fault. I kept hounding him for it, and we were both just...we wanted it.”

Toriel sighs, rubbing her temple as she turns to the younger of her children. “I never said you were blameless, Frisk. But you are human, and Asriel is not. I have talked to him about the kind of preparations he would need to do if you two were to...enjoy yourselves, as you did.”

Asriel interrupts his mother, silently hoping that in itself wouldn’t cause him more problems. “Mom. I know the precautions. But if Frisk has never had anyone do anything like that before, and neither have I, why would we have to use any protections?”

Toriel fumes, exhaling heavily before looking toward Asriel. “Because, Asriel, you are a monster. Monsters do not work in the same way that humans do, especially when it comes to things like sex. When a male monster copulates with a human, regardless of that human’s gender, there are a lot of complications that could arrive. You know that.”

Asriel swallows hard, nodding weakly. “I do. I just forgot, Mom. It was really hard to focus okay?” The disappointed look on Toriel’s face was all the proof he needed. He knew that he had made mistakes but hadn’t expect the ramifications to be this severe.

“I understand, Asriel. I do, and it’s...well, it isn’t fine. You may have caused serious problems for Frisk. I’ll have to give them a thorough examination at the very least. The risk of magical seepage alone could play havoc with their SOUL.” Toriel pulled Frisk aside as gently as she could. “I’ll have to look into this. Asriel, please just...go. Go somewhere else, and think about the danger you caused by not thinking further ahead.”

Asriel opened his mouth to retort, but closed it again, nodding silently as he turned and walked out of the living room, fighting back tears as he fled upstairs to his bedroom. He knew that he should have been more careful with Frisk. He knew monsters worked differently than humans, but he had felt too possessive to care. Proving that Frisk was his was so dominant in his mind that he hadn’t thought to use any safeguards.

“Mom, please don’t be mad at Asriel.” Frisk pleaded, pulling nervously at the hem of their tshirt, an old striped one that matched the one they had worn years prior in the Underground. “I know we messed up, but-”

“Frisk, please. I understand that you want to stand up for him, but Asriel knows what he did.” Toriel’s tone is short, her anger clearly being restrained. “Now, please hold still. I need to see your SOUL, to see if what happened affected it at all.”

Frisk nods, swallowing hard. Since they had left the Underground, Frisk had done their best to avoid triggering encounters that brought their SOUL free of their body. It was all they could do not to panic as the world went black around them and Toriel, a bright red heart floating a few inches in front of their chest. Looking down toward the very embodiment of themselves, Frisk couldn’t help but gasp as they saw that the red heart had a splinter of white in it. The shock of seeing the purest expression of their existence with a painfully visible imperfection was too much for them to handle, and the world went completely dark as they fell unconscious.

Everything hurt as Frisk regained their senses, their head pounding as they weakly opened their eyes. They were in their bedroom, somehow, and Frisk could barely remember how they got here. Something about an encounter with Toriel, and their SOUL, and-

Frisk swallowed hard as memories came crashing back. Their SOUL was broken. Well, not broken, but there was something wrong with it. It was turning white, like a monster’s SOUL. It must have been caused when Asriel had made love to them, but there was no way Frisk could ever have comprehended the possiblity that it would change them so intrinsically.

Pushing themselves up into a seated position, Frisk clutched the side of their head in pain, an angry pulsing pain behind their eyes. This felt far too similar to having their SOUL shattered, in the moments before Frisk had been forced to LOAD.

Groaning in pain, Frisk struggled to push themselves out of bed, wobbling on their feet as they stumbled over to the doorway, weakly grabbing the door and pulling it open, nearly falling back as the door swings open. They hadn’t felt this weak since the one time they ended up with a nasty case of the flu about eighteen months back.

Frisk leant heavily against the wall as they started to walk down the stairs, but halted a few steps down as they overheard their parents talking.

“Tori, you’re worrying too much. Frisk’s SOUL is changing because of Asriel, sure, but unless I see fur and horns sprouting from them, it’ll probably be fine.” Sans sounded as cavalier about this as he did everything, but Frisk couldn’t help reaching up to check if any horns had magically grown from their head when they’d been out.

Breathing a heavy sigh of relief when they found nothing, Frisk tried to listen in further to the conversation that was happening downstairs.

“Sans. You said it yourself, Frisk is heavily permeated with magic because they live with us all. Between myself, Asriel and you, we are some of the most magically capable monsters alive.” Toriel sounded much more concerned, and Frisk sat upon the stairs, assuming this conversation may take some time.

“I know, Tori. But Frisk’s a human, they can’t do magic. I know you’re worried. I am too, y’know. If it’ll put your mind to rest, I’ll see what I can find out.” Frisk leant their head against the wall. Were the things their mother was suggesting even possible? Becoming a monster, or gaining the ability to use magic? If they could, what kind of magic would they even use?

Questions running through their mind, Frisk pushed themselves onto their feet, slowly going down the remainder of the stairs, knocking on the living room door so as not to surprise their parents.

Toriel startled, shaking her head lightly as she turned to Frisk, smiling weakly. “It is good to see you awake, my child. You worried me, falling unconscious so suddenly.” Frisk laughed nervously, scratching at the back of their neck as Toriel continued. “You do not need to stan in the doorframe, come and sit. You should not have moved so much already.”

Wondering if their expression showed just how intensely grateful they were, Frisk stumbled over to the couch and slumped upon it, still cradling their head in their hand. The pain behind their eyes was still very intense, and they could barely hold back a wince as Sans spoke, his voice louder with the decreased distance between them.

“Why did you get out of bed, kiddo?” Sans questions softly, getting out of his chair and walking over to them, placing the back of his bony hand against their forehead. Frisk had no idea how Sans could possibly tell the temperature that they had, but somehow Sans seemed every bit as capable of it as Toriel was. “You’re still running high fever. C’mon, let’s get you back into bed. Tori, can you call Asriel, let him know that Frisk woke?”

Frisk groaned quietly, standing from their seat and leaning against Sans for suppport. “Wait, how long was I out? You make it sound like it was days.”

The silence that lingers after Frisk’s statement was more than a little worrying to the human. “It can’t have been days, right? Mom? D-Dad?” They tense up slightly, eyes wide from nerves. Now that they thought about it, Frisk had never lost an encounter in this way before. Maybe instead of dying this time, they just fell into a very deep sleep or something.

“It has been almost two days, my child. The shock of seeing your SOUL altered in such a way must have caused you more harm than I could have anticipated. I am sorry, Frisk. Truly.” Frisk couldn’t bear to look at Toriel, and the guilt that clearly wracked the poor goat-woman’s mind.

“Mom, it’s fine. It was just a shock, I guess. I mean, I didn’t expect that being with Asriel would literally turn me part-monster.” Frisk shrugs, a small nervous smile on their face. “It’ll only be a one-time thing though right? My SOUL won’t go more and more white every time we...well. You get it.”

Toriel smiles at the soft pink tinting to Frisk’s cheeks. “Providing Asriel pays enough attention to properly protect the two of you, yes, this should only happen once. Unless, of course, you wanted to become one of us.”

Frisk almost fainted again, then and there. They couldn’t even summon the words for an answer, so simply gave a defeated sigh and a shake of their head. If that kind of thing was even possible, it would require weeks, if not months of consideration.

“Think on it, kid. It isn’t all bad, being magical. And you wouldn’t get old, either. You and Asriel would be Boss Monsters together, after all. Just like Tori and me.” Sans said, his tone sincere as he walks with Frisk, aiding them up the stairs by hand instead of magical interference. Even he wasn’t sure how sensitive the young human would be to any magic involvement.

“Dad, I’m sixteen. I can’t go making life decisions before I even graduate.” Frisk replies with a soft sigh. They’d made a very important life decision when they were ten, but that was a long time ago and their life was very different now. They were happy. They wanted the life they had, not a new one as a monster, even a Boss Monster.

“Up to you, kiddo. Nobody’s gonna make you do anything you don’t wanna do.” Sans grins, pushing open the door to Frisk and Asriel’s shared bedroom before leading Frisk to the bed, lying them down upon it. “Alright. No more getting out of bed.”

Frisk sighed dramatically, throwing their hands into the air. “What a curse, to be unable to leave this comfortable, blanket-laden bed. Whatever shall I do?” Frisk smiled at the laugh that got from Sans, even if their chest hurt from all the speaking they had done since they had awoken.

“Get some rest, kid. I’ll let Asriel know how you are when he gets home, alright?” Sans pushed some hair away from Frisk’s face, trying not to flinch too hard when he noticed the roots of their hair had started to go white. 

Frisk nodded, not noticing their father shifting suddenly as he left, the door clicking closed behind him. The quiet gave Frisk a chance to think things over, to try and understand what exactly was going on.

Asriel had, apparently, not used some kind of protection that Frisk had to assume was magical, and somehow that had caused Frisk’s SOUL to change; for a part of it to become white, like the SOUL of a monster. So all Frisk could assume was that it must have been caused when Asriel had made love to them.

Frisk sighed deeply, shifting to get more comfortable. It was a simple concept but Frisk didn’t want to accept it. Their SOUL was really the only thing they had that connected them to being human. If they lost that, then they didn’t really have anything left.

Frisk hated that they couldn’t tell if that was a bad thing or a good thing. They had never liked being human. Humanity always felt like a tether, a label they didn’t really want to have. That was why they’d gone to Mt Ebott after all.

But now, faced with the chance to stop being human, they weren’t sure they wanted that anymore. They liked being different to the rest of their family. They liked being the human in the family of monsters, in the town mostly full of monsters.

It made them special, and they needed to be special. They needed to have something to hold onto. And being human amongst monsters was that thing. But the chance to be a monster, to become something so much more than human, was incredibly tempting.

Frisk found themselves very glad of Asriel’s arrival, both to see him and to have something other than their own thoughts to focus on, as they seemed to be going in a very confusing spiral.

The warmth of Asriel’s fur when the caprine hugged them was a welcome anchor from their thoughts. It brought them back into reality, bringing the world back into focus as they wrapped their arms around Asriel, holding him close and breathing in his scent.

He helped. The thoughts that scared them were gone when he was here. He loved them no matter what, and they loved him just as much.

“Frisk, I’m so glad you’re awake.” Asriel’s voice was shaky, and scared. Frisk hated seeing him scared. Frisk was only human, and they couldn’t do anything for him. He helped, but him being scared was a problem.

“Are you okay? You just passed out after that encounter with Mom, and-” Frisk had to cut him off before Asriel worried himself to an illness as bad as their own. They moved their hands, taking hold of the caprine’s horns and kissing him gently, for a brief moment.

“I’m okay, Asri. Tired, and I have a fever, but I’m okay.” Frisk says, smiling weakly as they let go of their brother’s horns, shifting out of the way and patting the mattress beside them. “Lie down. I want hugs.”

Asriel laughed softly, climbing onto the bed and cuddling Frisk close, holding them up against him. His heart was pounding from the relief that Frisk had woken up from the sudden sleep they’d fallen into, and he wanted to hold them as close as he could.

“Mom explained what happened. I promise I’ll be more careful from now on.” Asriel lowered his voice to a whisper, unsure of how Frisk’s head was. “I won’t take away any more of your SOUL, I promise.”

Frisk nodded weakly, curling their fingers in Asriel’s fur. He was soft, and he was warm. Asriel was all they could focus on. They couldn’t let their thoughts pull them away from the world again.

The pair stayed as they were for as long as they could bear, before finally detangling from each other. Asriel gently drew his claws through Frisk’s hair, placing a kiss on their forehead. “I’m glad you’re okay, Frisk.”

Frisk nods weakly. “I feel good. Better, at least. Thanks, Asri.” They hug him tightly one more time before pushing themselves up into a seated position. “Dad said I wasn’t allowed to get out of bed. But I can read or something if you want to go talk to them, or whatever. I don’t mind.”

Asriel pushed himself upward as well, sitting beside Frisk. “I’m good sitting here with you. We can talk, if you want. Or I can cuddle you.” Asriel looked down toward Frisk, gently nudging them with his shoulder. They seemed happy, which relieved Asriel greatly.

“I’d like to talk. Talking sounds like fun, providing you can keep your mind out of the gutter for any amount of time.” Frisk teased, leaning against their older brother, closing their eyes and breathing out slowly. “I’m too ill to be talking about sex.”

Asriel smiles, wrapping his arm around them. “I can’t make any promises, Frisk. But I’ll do my best.” He couldn’t help but notice when Frisk shifted against them, almost as if they were uncomfortable with his grip.

“Something wrong, Frisk? You seem uncomfortable.” He tried not to sound too overly-concerned, knowing that Frisk didn’t like it when Asriel acted in those kinds of ways. It hinted at how Asriel was starting to struggle with how possessive he was feeling toward Frisk, and Frisk knew it.

“Huh? No, just trying to sit more comfortably. You worry way too much, Asri.” Frisk replied, smiling slightly. “I already have one goat-monster acting motherly while I feel ill, let’s not make it two, okay?”

Asriel pouted, tempted to push Frisk before realising that could be dangerous. “C’mon, Frisk. You get sick so rarely that it’s really worrying when you do. And knowing it’s my fault really doesn’t make it any easier.”

Frisk nuzzled against Asriel, hoping it wasn’t too obvious when they inhaled deeply to take in his scent. The way Asriel smelt always brought a sense of calm to them, even if it Frisk always felt very embarrassed when they thought about those kind of things. “You didn’t do it on purpose, Asri. How could we have known?”

Asriel tightened his grip, shifting and throwing his weight over Frisk so he was knelt over them, not quite straddling them as he looked into their eyes. “Frisk. I didn’t take enough precautions, and it literally made you a different person, even if it was only a very small change.”

Frisk cowered slightly, Asriel’s impressive size all the more apparent in this position, one Frisk absentmindedly noticed was one they’d never found themselves in before. Their brother’s presence was more than a little imposing, and Frisk couldn’t help but lean back and rest their hands on the bed, swallowing hard and trying as best they could to push any dirty thoughts from their head. Their stupid over-active libido was an absolute curse at times like this.

“I’m serious, Frisk. I changed you, because I didn’t pay enough attention. I was so hung up on having sex with you that I made you different. I can’t do that again.” Asriel did all he could to restrain himself from shouting, instead showing his desperation through his tone of voice, not even embarrassed as he heard it crack.

Frisk smiled softly, bringing their hand up to Asriel’s cheek and stroking it slightly. “Asriel. I don’t feel different. I don’t care if I’m different. I don’t regret what happened, in the slightest. I love you, okay?”

Asriel tried to smile. He did, but he couldn’t bring himself to. He felt far too guilty about what had happened, even if Frisk seemed to be fine with it. Frisk obviously hadn’t noticed it, but there were a few white hairs interspersed amongst the brown. What else had changed, Asriel didn’t know; but even a small detail like that crushed Asriel. “I’m sorry, Frisk. I love you too, alright?” 

Frisk’s smile faltered slightly, before they wrapped their arms around Asriel, hoping to reassure him as best they could. Frisk knew, deep down, that they were terrified of what might happen to them if this happened again, if they started becoming less and less human. But they hadn’t. This happened once and it hadn’t done anything, at least as far as they knew.

Asriel grunted quietly, a soft laugh escaping him as he returned Frisk’s gesture, wrapping the small human in his arms and holding them closely. He loved Frisk more than almost anyone else alive, and he found himself struggling constantly with the idea that they would never be the same anymore because of something he had done.

“It’s alright, Asri. As long as we’re careful, we can do this stuff again. And I want to do it again.” Frisk spoke quietly, partially from being muffled by Asriel’s fur, and partially from fear of being overheard.

Asriel smiled despite himself, resting his chin upon Frisk’s head as he tightening his grip more, cursing internally when he heard the quiet tearing of Frisk’s pajama top as his claws punched through it. He really needed to remember how long his claws were getting.

“Really, Asri? We’re having a moment here and you decide to break my shirt? I told you I was still too sick to do anything sexual.” Frisk chided, weakly headbutting Asriel in the chest. “Stop trying to take advantage of my stupid libido, you big caprine jerk.”

Asriel froze, leaning away from Frisk and holding them at arms length, a questioning expression on his face. “Your whatnow? You never said there was anything wrong with your libido.”

Frisk’s eyes widened, a deep red blush flaring on their cheeks as they laughed nervously, regretting that they were pinned by Asriel so that they couldn’t just run away and escape. “Y-yeah. My sex drive is a little...enthusiastic. I get aroused really easily, and it’s hard for me to come down from it.”

Asriel smiled softly, leaning forward and kissing Frisk’s forehead gently. “I’ll have to be more careful around you then, won’t I? Unless, that is, you enjoy getting teased.” He knew he shouldn’t be doing this to Frisk in the state they were in, but Asriel never was very good at controlling himself.

“Don’t you dare, Asri. My head is still pounding, I can’t deal with this right now.” Frisk resisted, pulling their arms free of Asriel’s grip and trying to squirm out from underneath the caprine, only to find that the single thing they didn’t want to happen, did. Pushing pressure up against Asriel, straddling them as he basically was, sent hot rushes through Frisk’s body, causing them to lock up and stay as still as they could.

Asriel laughed softly, kissing Frisk on the forehead again before shifting his weight and moving off of Frisk, sitting down beside them. “Relax, Frisk. I know you’re ill, even if you seem to be recovering pretty quick. I won’t tease you whie you’re in this state, don’t worry.”

Frisk breathed a deep sigh of relief, leaning against their brother again. “Alright, thanks Asri. Then what else wo-”

Asriel put a furred finger to Frisk’s lips, winking at them as he did so. “That doesn’t mean I won’t do more than teasing.” The look of embarrassed half-anger in Frisk’s expression was more than Asriel could handle, and he couldn’t stop himself from laughing. “I’m kidding! Jeez, what do you take me for?”

Frisk pouted, crossing their arms over their chest as they did so. “Don’t be an ass, Asri. A-and now I’m all flustered and stuff too, you jerk!”

Cuddling Frisk closely, Asriel gently tangled his fingers in their hair, making sure to keep his claws as far from Frisk’s scalp as he could. “I’m sorry, alright? You’re just far too cute when you get embarrassed. Just, uh, don’t tell Mom alright? She told me I wasn’t allowed to tease you while you were ill.”

Frisk sighed quietly, leaning more into Asriel and closing their eyes to try and relax. “Fine. You might be a jerk but I can’t get you in trouble.”

“You’re the best, Frisk.” Asriel smiled, kissing Frisk’s temple softly. “When you’re feeling better, I’ll make it up to you, alright?”

“You better. And not in a dirty way either, you pervert.” Frisk chided tiredly, feeling consciousness slipping from them by the moment.

It wasn’t much later that Asriel, smiling softly, carefully untangled himself from Frisk and laid the still-sickly human down, covering them and gently kissing their forehead before standing and leaving the bedroom, gently closing the door behind him and exhaling deeply as he did.

Asriel decided then, in that moment, that he finally understood what it meant to want to spend your life with someone. Not that he’d tell Frisk that, of course. He knew that they loved him and that they knew he loved them, but this was something a little more than that.

He only hoped that someday Frisk would want the same amount of commitment as Asriel now believed he himself wanted.


	5. Chapter 5

**Notes for the Chapter:**

> Hey, Aithe here. Sorry for another short chapter, I just wanted to get out a little more plot, I guess. Next chapter will definitely have a lot more 'action' in it than these past couple have. As always, feedback is appreciated and I hope you enjoy!

Frisk very nearly panicked when they noticed the thin white streaks that now ran through their hair. The only thing that stopped them from doing so was the fact that they were the first one awake, and waking up their family by freaking out wasn’t exactly the best way to get into their good books.

They almost looked like highlights, in a way. If Frisk cared in any way about looking fashionable, they would think it looked rather nice; even if there was no real pattern to how the hair was colored now. Frisk did, however, realise that it made them look a little more like Asriel. The white hair would perfectly match his fur, if they were stood side-by-side. 

Freezing for a moment in panic, Frisk pulled the waistband of their pajama pants forward, an intensely red blush forming on their cheeks when they found that it wasn’t just the hair on their head that had changed color. Letting the waistband go, Frisk dragged their hands through their hair and sighed quietly. There was no way in hell that Asriel wouldn’t tease them for that.

Walking through to the kitchen and opening the fridge, Frisk hummed quietly to themselves as they thought about what had happened. They could remember well enough now that they had collapsed after discovering what had happened to their SOUL. They still weren’t sure what to think of it. They didn’t feel any different, and the only external change seemed to be purely cosmetic.

But they were, at least technically, part-monster now. Sure they didn’t have horns or magic or whatever else, but their SOUL was no longer that of a human. The white sliver in it had proven that. Frisk wasn’t sure they minded, but wasn’t sure how much change they’d be willing to go through with.

A welcome distraction from their thoughts came in the form of a sudden but very warm hug from behind. Almost instinctively leaning back into it, Frisk smiled slightly, although found some surprise in that it was Toriel who had hugged them, not Asriel, who normally woke before their mother did.

“Good morning, my child. It is good to see you up and about.” Toriel’s motherly tone almost made Frisk melt into the hug, no matter how embarrassing it would be. Frisk may love Asriel’s hugs but they couldn’t compare to those given by the much taller, much softer Toriel.

“Thanks Mom. I feel a lot better now.” Frisk spoke quietly, their throat somewhat sore from lack of hydration. “I’m just finding some breakfast, did you want anything?”

Toriel smiled, tightening her grip on Frisk for a moment before letting them go. “I will be fine, thank you. Make yourself whatever you like.” Toriel then walked over to the table, sitting down at it as she watched Frisk walk around aimlessly, either very tired or very distracted. “Is something wrong, Frisk?”

Frisk paused, turning to Toriel and leaning against the kitchen counter. “Hm? No, Mom, I’m alright. Just thinking, really. About, yknow. This.” They gesture to the new coloring to their hair. “Trying to figure out what it means.”

Toriel nodded, a small and nervous smile on her face. “I understand it must be confusing. I cannot imagine any other human has undergone such changes before, after all. Most humans aren’t anywhere near as receptive to magic, or monster SOULs after all.”

Frisk tilted their head slightly in confusion. “I’m different to most humans?” In truth, Frisk had always assumed as much but that was mostly because of what had happened when they were young. They couldn’t think of any other human who could have done what they did, after all.

“Yes, you are. Perhaps it is a side-effect of having been around magical beings for as long as you have, but you seem to be especially receptive to magic.” Toriel explained, following Frisk as they walked over to the table and sat opposite her. “‘I’m honetly surprised that you haven’t yet learnt how to cast magic in some way.”

Frisk leant forward, resting their elbows on the table and pulling at their hair, a habit they’d gotten into when they were restless or nervous. Or both, as they were now. “I haven’t really tried. I’m not monster enough to have thought about it. All that’s changed is my hair, after all.”

Toriel nodded, smiling warmly. “And it looks wonderful on you, I might add. But please, Frisk, do not think that I am trying to pressure you into deciding just yet. Whether you wish to remain human or slowly become more like us, I will support you. So will your father, and of course Asriel will too.”

Frisk paled slightly, looking up to Toriel with panicked confusion on their expression. “Wait, what? You’re saying I could actually turn into a monster if, uh...what made this happen, happened again?”

Toriel laughed softly at Frisk’s continued nervousness about the subject, but nodded softly. “Yes, it could. If you and Asriel continued to have sex without any form of protection for your SOUL, it may well continue to change.”

Frisk unintentionally grabs at their chest, as if their SOUL was showing right now. The thought of being in control of such a huge transformation was intimidating in a way. Even more so considering that they still had no idea whether or not they even wanted to change any further.

“But that is rather a heavy subject so early in the morning, is it not?” Toriel reached over the table, taking Frisk’s hand in her own. “If you want to talk about it, perhaps we can do so later. I may not know too much, but I will help however I can.”

Frisk nodded, managing to smile weakly. “Thanks, Mom. I’m sorry for causing all this trouble for everyone.”

“Nonsense, my child. It was hardly responsible of me to assume that you and Asriel wouldn’t do this kind of thing eventually. You are of that age now, after all.” Toriel spoke carefully, trying not to embarrass Frisk too much. At least not intentionally.

“Mom, I really don’t want to talk about it. It’s weird enough talking to Asriel about it, and he isn’t...yknow. You.” Frisk pulls their hand away from Toriel’s, coiling their hair around their fingers and pulling on it gently, grounding themselves on the numbing ache that it brought to them.

Toriel laughed softly, standing from the table and pushing her chair back into place. “Of course, Frisk. Not many people, monster or human, are comfortable talking like that with their mother, after all.”

The two made pleasant conversation while preparing breakfast, but after a short while Frisk leant heavily against the counter, a wave of lightheadedness washing over them. Exhaling sharply, Frisk gripped the counter hard enough to turn their knuckles white as the room started spinning around them.

“Frisk? Frisk, are you okay?” Toriel gently placed her hand on Frisk’s shoulder, concern clear on her face. Frisk had always been very healthy, so seeing this was more than a little worrying.

Swallowing hard, Frisk shook their head. “I’m alright, Mom. Just dizzy for some reason.” Frisk turned, leaning back against the counter and closing their eyes. “Don’t worry, alright?”

Toriel nods weakly, continuing to prepare breakfast for the family as Frisk recovered. They obviously weren’t fully recuperated from their collapse, or so it seemed. But they were nearly an adult now, and Toriel couldn’t constantly mother them about every little thing.

Much to both Toriel and Frisk’s relief, the dizziness passed relatively quickly. Frisk breathed deeply, swallowing down the nausea that the dizziness had brought. “Alright, I think I’m okay now. That was weird.”

“Your body is still reacting to the new monster parts, most likely.” Sans’ voice appeared from nowhere, and Frisk looked up to see that somehow the skeleton had come downstairs and sat at the table without making a single sound. Frisk hated how easily he did that. “Even if there’s only a little bit of monster in you, your human body is trying to figure out how to work alongside it.”

Fighting the urge to point out there was quite a lot of monster inside them at one point, Frisk simply nodded. It made sense, after all, that something like that would be the case.

“How’s the new hairstyle suiting you anyway kiddo? You’re really starting to look like family now, huh?” Sans joked, winking at Frisk as he did so. Frisk still, after all these years, had no idea how that worked. They gave up questioning how monsters worked a long time ago.

“Sans, don’t tease Frisk. They have enough going on as it is.” Toriel chided, glaring at Sans as she did so. Sans leant back against his chair, shrugging weakly as Toriel turned to Frisk, her expression softening. “Just ignore him, Frisk. If you’re still feeling dizzy, perhaps you should go and rest?”

Frisk shook their head, wincing slightly as the motion caused a small, short bout of dizziness again. “Mom, I just got out of bed. I feel fine, just a little lightheaded. Please don’t worry so much.”

Toriel relented, sighing quietly. “Alright, I won’t force you. But I shouldn’t have to remind you that you aren’t fully recovered yet which means you need to behave around your brother.”

“Mom!” Frisk said in mock-outrage, hoping it would mask their intense embarrassment as they crossed their arms over their chest. “A-and beside, you should be telling Asriel to behave, not me.”

“Hmm, perhaps that is true. After all, you could hardly have covered your neck in that many bruises by yourself, could you?” Toriel teased, causing Frisk to turn even more red and look away from her. “I’m almost impressed with his handiwork, honestly. There’s not a lot of your neck that isn’t purple, or red, or blue, or any combina-”

“Mom, stop!” Frisk nearly yelled, feeling on the verge of an embarrassment-fulled breakdown. “Could you be any more gross right now?”

Frisk’s embarrassment, now causing a dull aching in their chest, was slightly assuaged when Asriel came up behind them, wrapping his arms around the human’s chest. “C’mon, Mom, don’t tease Frisk like that.”

Toriel smiled widely, getting back to work on the breakfast. “I’m sorry, Frisk. But, Asriel, Frisk is right. While they’re recovering, you need to behave yourself.”

Asriel blushed slightly, an awkward smile on his face. “I’ll do my best, Mom. And I’ll try not to end up bruising their neck too much next time, either.”

Frisk felt like they wanted to die of embarrassment. Asriel was bad enough when he was teasing them, but they’d never expected such things from Toriel. She had always seemed so light-hearted in her joking, but Frisk couldn’t help but assume there was more to it this time.

“I hate all of you. You’re all jerks.” Frisk pouted, their arms crossed tightly in front of them. When Asriel reacted by ruffling their hair, Frisk swatted uselessly at him before sighing in defeat.

“Relax, Frisk. You know we don’t mean anything by it.” Asriel reassured them, hugging them tightly as he did so. “Oh, uh, Mom? Do you mind if I talk to Frisk real quick?”

Toriel paused, looking toward her eldest child. “Providing all you do is talk, you’re welcome to do so. Just be sure to be back in here before breakfast gets cold.”

Asriel nods, half-dragging Frisk out of the kitchen as the human finally catches up with what was going on. “W-wait, Asri, what-”

Frisk’s questioning was cut off when Asriel pushed them up against the wall of the living room. “Frisk. I was listening to what you and Mom were talking about. Are you seriously considering becoming a monster?”

Frisk cowered slightly, swallowing hard as they realised Asriel had trapped them. Trying not to look as panicked as they felt, Frisk looked up to meet Asriel’s gaze. “I don’t know. Why?”

“Wh--you can’t be serious. Why? Frisk, you’re thinking about becoming a monster. That’s a permanent thing, there’d be no going back.” Asriel sounded almost like they were pleading Frisk, his claws scratching slighty at the paint on the living room walls. “And if such a small change like your hair has made you feel like this, you might not even...”

As Asriel trailed off, Frisk swallowed hard, barely having the courage to speak. “Asri. If I do make any choices about it, it wouldn’t be for a long time. But either way, Asriel, I’m allowed to make my own decisions. And if that decision means that I become a Boss Monster so that I can be with you longer than my human lifespan would let me, that’s what that decision means.”

Asriel paused, stepping back from Frisk, who themselves leans back against the wall, finally able to relax slightly. “That’s the only reason I’ve been thinking about it, Asri. I know, I’m getting ahead of myself and acting kind of stupidly. But you make me happy. And I want to be happy for as long as I can.”

Asriel sighs quietly, rubbing his temples. “Frisk, you’re being stupid. You...you can’t just assume that things like this are safe, or that they’ll work. Or anything about this, or us.” He tried not to sound too scathing, but wasn’t sure that was working. “Listen. I’m glad you’re happy with me. But you can’t just make stupid decisions because of me.”

Frisk curled up slightly, Asriel’s beration making them feel very small and insignificant. He was right, of course. But that didn’t make it any easier. They were being stupid, acting like a child. 

“I love you, Frisk, don’t think otherwise. But I love you for you. Changing to a monster won’t change that, and nor will staying human.” Asriel continued, his expression softening. “I’m not saying you shouldn’t make this choice. But make it a long time from now. When we’re properly commited.”

Frisk nodded weakly, sniffling and rubbing their nose with the back of their hand. “Got it. Jeez, I never thought you’d be the voice of reason here.”

Asriel smiled, laughing quietly as he embraced Frisk, kissing them gently on the forehead. “There’s a first time for everything, isnt there? Now, c’mon. We have breakfast to eat. And maybe if you’re feeling better later today, I can eat you too.”

Frisk headbutted Asriel’s chest. “Behave yourself, Asri. You’ll get both of us in trouble.”

“I don’t hear you saying no, Frisk.”


	6. Decisions, an argument, and a new way to make up.

**Notes for the Chapter:**

> Hey, Aithe here. This chapter's a little different from the others. I wanted to try and flesh out Asriel and Frisk as characters a little here, so I hope you guys like what I'm doing with things. As always, feedback is greatly appreciated and I hope you enjoy!

Frisk very nearly panicked when they noticed the thin white streaks that now ran through their hair. The only thing that stopped them from doing so was the fact that they were the first one awake, and waking up their family by freaking out wasn’t exactly the best way to get into their good books.

They almost looked like highlights, in a way. If Frisk cared in any way about looking fashionable, they would think it looked rather nice; even if there was no real pattern to how the hair was colored now. Frisk did, however, realise that it made them look a little more like Asriel. The white hair would perfectly match his fur, if they were stood side-by-side. 

Freezing for a moment in panic, Frisk pulled the waistband of their pajama pants forward, an intensely red blush forming on their cheeks when they found that it wasn’t just the hair on their head that had changed color. Letting the waistband go, Frisk dragged their hands through their hair and sighed quietly. There was no way in hell that Asriel wouldn’t tease them for that.

Walking through to the kitchen and opening the fridge, Frisk hummed quietly to themselves as they thought about what had happened. They could remember well enough now that they had collapsed after discovering what had happened to their SOUL. They still weren’t sure what to think of it. They didn’t feel any different, and the only external change seemed to be purely cosmetic.

But they were, at least technically, part-monster now. Sure they didn’t have horns or magic or whatever else, but their SOUL was no longer that of a human. The white sliver in it had proven that. Frisk wasn’t sure they minded, but wasn’t sure how much change they’d be willing to go through with.

A welcome distraction from their thoughts came in the form of a sudden but very warm hug from behind. Almost instinctively leaning back into it, Frisk smiled slightly, although found some surprise in that it was Toriel who had hugged them, not Asriel, who normally woke before their mother did.

“Good morning, my child. It is good to see you up and about.” Toriel’s motherly tone almost made Frisk melt into the hug, no matter how embarrassing it would be. Frisk may love Asriel’s hugs but they couldn’t compare to those given by the much taller, much softer Toriel.

“Thanks Mom. I feel a lot better now.” Frisk spoke quietly, their throat somewhat sore from lack of hydration. “I’m just finding some breakfast, did you want anything?”

Toriel smiled, tightening her grip on Frisk for a moment before letting them go. “I will be fine, thank you. Make yourself whatever you like.” Toriel then walked over to the table, sitting down at it as she watched Frisk walk around aimlessly, either very tired or very distracted. “Is something wrong, Frisk?”

Frisk paused, turning to Toriel and leaning against the kitchen counter. “Hm? No, Mom, I’m alright. Just thinking, really. About, yknow. This.” They gesture to the new coloring to their hair. “Trying to figure out what it means.”

Toriel nodded, a small and nervous smile on her face. “I understand it must be confusing. I cannot imagine any other human has undergone such changes before, after all. Most humans aren’t anywhere near as receptive to magic, or monster SOULs after all.”

Frisk tilted their head slightly in confusion. “I’m different to most humans?” In truth, Frisk had always assumed as much but that was mostly because of what had happened when they were young. They couldn’t think of any other human who could have done what they did, after all.

“Yes, you are. Perhaps it is a side-effect of having been around magical beings for as long as you have, but you seem to be especially receptive to magic.” Toriel explained, following Frisk as they walked over to the table and sat opposite her. “‘I’m honetly surprised that you haven’t yet learnt how to cast magic in some way.”

Frisk leant forward, resting their elbows on the table and pulling at their hair, a habit they’d gotten into when they were restless or nervous. Or both, as they were now. “I haven’t really tried. I’m not monster enough to have thought about it. All that’s changed is my hair, after all.”

Toriel nodded, smiling warmly. “And it looks wonderful on you, I might add. But please, Frisk, do not think that I am trying to pressure you into deciding just yet. Whether you wish to remain human or slowly become more like us, I will support you. So will your father, and of course Asriel will too.”

Frisk paled slightly, looking up to Toriel with panicked confusion on their expression. “Wait, what? You’re saying I could actually turn into a monster if, uh...what made this happen, happened again?”

Toriel laughed softly at Frisk’s continued nervousness about the subject, but nodded softly. “Yes, it could. If you and Asriel continued to have sex without any form of protection for your SOUL, it may well continue to change.”

Frisk unintentionally grabs at their chest, as if their SOUL was showing right now. The thought of being in control of such a huge transformation was intimidating in a way. Even more so considering that they still had no idea whether or not they even wanted to change any further.

“But that is rather a heavy subject so early in the morning, is it not?” Toriel reached over the table, taking Frisk’s hand in her own. “If you want to talk about it, perhaps we can do so later. I may not know too much, but I will help however I can.”

Frisk nodded, managing to smile weakly. “Thanks, Mom. I’m sorry for causing all this trouble for everyone.”

“Nonsense, my child. It was hardly responsible of me to assume that you and Asriel wouldn’t do this kind of thing eventually. You are of that age now, after all.” Toriel spoke carefully, trying not to embarrass Frisk too much. At least not intentionally.

“Mom, I really don’t want to talk about it. It’s weird enough talking to Asriel about it, and he isn’t...yknow. You.” Frisk pulls their hand away from Toriel’s, coiling their hair around their fingers and pulling on it gently, grounding themselves on the numbing ache that it brought to them.

Toriel laughed softly, standing from the table and pushing her chair back into place. “Of course, Frisk. Not many people, monster or human, are comfortable talking like that with their mother, after all.”

The two made pleasant conversation while preparing breakfast, but after a short while Frisk leant heavily against the counter, a wave of lightheadedness washing over them. Exhaling sharply, Frisk gripped the counter hard enough to turn their knuckles white as the room started spinning around them.

“Frisk? Frisk, are you okay?” Toriel gently placed her hand on Frisk’s shoulder, concern clear on her face. Frisk had always been very healthy, so seeing this was more than a little worrying.

Swallowing hard, Frisk shook their head. “I’m alright, Mom. Just dizzy for some reason.” Frisk turned, leaning back against the counter and closing their eyes. “Don’t worry, alright?”

Toriel nods weakly, continuing to prepare breakfast for the family as Frisk recovered. They obviously weren’t fully recuperated from their collapse, or so it seemed. But they were nearly an adult now, and Toriel couldn’t constantly mother them about every little thing.

Much to both Toriel and Frisk’s relief, the dizziness passed relatively quickly. Frisk breathed deeply, swallowing down the nausea that the dizziness had brought. “Alright, I think I’m okay now. That was weird.”

“Your body is still reacting to the new monster parts, most likely.” Sans’ voice appeared from nowhere, and Frisk looked up to see that somehow the skeleton had come downstairs and sat at the table without making a single sound. Frisk hated how easily he did that. “Even if there’s only a little bit of monster in you, your human body is trying to figure out how to work alongside it.”

Fighting the urge to point out there was quite a lot of monster inside them at one point, Frisk simply nodded. It made sense, after all, that something like that would be the case.

“How’s the new hairstyle suiting you anyway kiddo? You’re really starting to look like family now, huh?” Sans joked, winking at Frisk as he did so. Frisk still, after all these years, had no idea how that worked. They gave up questioning how monsters worked a long time ago.

“Sans, don’t tease Frisk. They have enough going on as it is.” Toriel chided, glaring at Sans as she did so. Sans leant back against his chair, shrugging weakly as Toriel turned to Frisk, her expression softening. “Just ignore him, Frisk. If you’re still feeling dizzy, perhaps you should go and rest?”

Frisk shook their head, wincing slightly as the motion caused a small, short bout of dizziness again. “Mom, I just got out of bed. I feel fine, just a little lightheaded. Please don’t worry so much.”

Toriel relented, sighing quietly. “Alright, I won’t force you. But I shouldn’t have to remind you that you aren’t fully recovered yet which means you need to behave around your brother.”

“Mom!” Frisk said in mock-outrage, hoping it would mask their intense embarrassment as they crossed their arms over their chest. “A-and beside, you should be telling Asriel to behave, not me.”

“Hmm, perhaps that is true. After all, you could hardly have covered your neck in that many bruises by yourself, could you?” Toriel teased, causing Frisk to turn even more red and look away from her. “I’m almost impressed with his handiwork, honestly. There’s not a lot of your neck that isn’t purple, or red, or blue, or any combina-”

“Mom, stop!” Frisk nearly yelled, feeling on the verge of an embarrassment-fulled breakdown. “Could you be any more gross right now?”

Frisk’s embarrassment, now causing a dull aching in their chest, was slightly assuaged when Asriel came up behind them, wrapping his arms around the human’s chest. “C’mon, Mom, don’t tease Frisk like that.”

Toriel smiled widely, getting back to work on the breakfast. “I’m sorry, Frisk. But, Asriel, Frisk is right. While they’re recovering, you need to behave yourself.”

Asriel blushed slightly, an awkward smile on his face. “I’ll do my best, Mom. And I’ll try not to end up bruising their neck too much next time, either.”

Frisk felt like they wanted to die of embarrassment. Asriel was bad enough when he was teasing them, but they’d never expected such things from Toriel. She had always seemed so light-hearted in her joking, but Frisk couldn’t help but assume there was more to it this time.

“I hate all of you. You’re all jerks.” Frisk pouted, their arms crossed tightly in front of them. When Asriel reacted by ruffling their hair, Frisk swatted uselessly at him before sighing in defeat.

“Relax, Frisk. You know we don’t mean anything by it.” Asriel reassured them, hugging them tightly as he did so. “Oh, uh, Mom? Do you mind if I talk to Frisk real quick?”

Toriel paused, looking toward her eldest child. “Providing all you do is talk, you’re welcome to do so. Just be sure to be back in here before breakfast gets cold.”

Asriel nods, half-dragging Frisk out of the kitchen as the human finally catches up with what was going on. “W-wait, Asri, what-”

Frisk’s questioning was cut off when Asriel pushed them up against the wall of the living room. “Frisk. I was listening to what you and Mom were talking about. Are you seriously considering becoming a monster?”

Frisk cowered slightly, swallowing hard as they realised Asriel had trapped them. Trying not to look as panicked as they felt, Frisk looked up to meet Asriel’s gaze. “I don’t know. Why?”

“Wh--you can’t be serious. Why? Frisk, you’re thinking about becoming a monster. That’s a permanent thing, there’d be no going back.” Asriel sounded almost like they were pleading Frisk, his claws scratching slighty at the paint on the living room walls. “And if such a small change like your hair has made you feel like this, you might not even...”

As Asriel trailed off, Frisk swallowed hard, barely having the courage to speak. “Asri. If I do make any choices about it, it wouldn’t be for a long time. But either way, Asriel, I’m allowed to make my own decisions. And if that decision means that I become a Boss Monster so that I can be with you longer than my human lifespan would let me, that’s what that decision means.”

Asriel paused, stepping back from Frisk, who themselves leans back against the wall, finally able to relax slightly. “That’s the only reason I’ve been thinking about it, Asri. I know, I’m getting ahead of myself and acting kind of stupidly. But you make me happy. And I want to be happy for as long as I can.”

Asriel sighs quietly, rubbing his temples. “Frisk, you’re being stupid. You...you can’t just assume that things like this are safe, or that they’ll work. Or anything about this, or us.” He tried not to sound too scathing, but wasn’t sure that was working. “Listen. I’m glad you’re happy with me. But you can’t just make stupid decisions because of me.”

Frisk curled up slightly, Asriel’s beration making them feel very small and insignificant. He was right, of course. But that didn’t make it any easier. They were being stupid, acting like a child. 

“I love you, Frisk, don’t think otherwise. But I love you for you. Changing to a monster won’t change that, and nor will staying human.” Asriel continued, his expression softening. “I’m not saying you shouldn’t make this choice. But make it a long time from now. When we’re properly commited.”

Frisk nodded weakly, sniffling and rubbing their nose with the back of their hand. “Got it. Jeez, I never thought you’d be the voice of reason here.”

Asriel smiled, laughing quietly as he embraced Frisk, kissing them gently on the forehead. “There’s a first time for everything, isnt there? Now, c’mon. We have breakfast to eat. And maybe if you’re feeling better later today, I can eat you too.”

Frisk headbutted Asriel’s chest. “Behave yourself, Asri. You’ll get both of us in trouble.”

“I don’t hear you saying no, Frisk.”

\--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Frisk often wondered if walking in on people showering actually happened. They’d heard about it, and seen it on tv and such. But that was all fictional.

That didn’t stop them from wondering whether, now that they were showering in an attempt to help clear the lingering headache and aching throughout their muscles, somebody might walk in. Or, more specifically, if that someone would be Asriel.

Frisk hadn’t truly realised just how perverse they truly were until they had started their relationship with Asriel. They couldn’t exactly claim to have been innocent before, but with Asriel things were different. Frisk wanted to do all kinds of things with Asriel. Or get Asriel to do all kinds of things to them.

Their mind wandering somewhat, Frisk leant against the bathroom wall, the hot water cascading over them. They exhaled deeply, closing their eyes peacefully as they allowed their mind to wander further, delving more deeply into the perverted thoughts they were currently having.

Thoughts of having Asriel over them, or being atop Asriel while he was inside them; thoughts of heat and pressure and intense, surging arousal. Before Frisk knew it, they had started toying with their semi-hard cock, teasing it to become fully hard as they swallowed hard, their eyes screwed shut so as to close out the outside world.

Panting and grunting quietly, Frisk continued masturbating, their thoughts drifting from one thing to another, before finally settling on one thing in particular - the idea of having Asriel toy with their SOUL. The thought of him gripping, stroking and licking their SOUL sent Frisk’s arousal into overdrive, the desperately horny human pleasuring themselves to a potent, messy orgasm, their semen hitting the tiled wall as they finally opened their eyes.

As Frisk tried to relax in afterglow, and the world came back into focus, they realised that they weren’t alone. At some point, while Frisk had been...entertaining themselves, Asriel had walked into the bathroom. He must have heard the water running, Frisk knew from experience that the waterflow was loud enough to be heard from outside the room.

“Enjoy yourself, Frisk?” Asriel teased, pushing off from the wall that he had been resting against, a rather obvious bulging in his pants. “You certainly seemed to be having fun, after all. And without me, too.”

Frisk, blushing heavily, turned away from Asriel and grabbed a bottle of bodywash to start cleaning themselves off, And the wall, too, when they were done. They wanted to shower for a reason, after all. And now that their head was spinning with both the fact that they had been caught, and then watched; and the fact that their headache felt all the worse for having enjoyed themselves.

Distracted by their dizziness, Frisk’s heart skipped a beat as they heard the glass door to the shower open, a rush of cold air flowing by them beore a very warm, furred embrace wrapped around their chest. “You don’t have to ignore me, Frisk.”

“W-what are you doing, Asri? You can’t be in the shower when I am.” Frisk’s voice was barely above a whisper, nervousness running through them as much as a burning curiosity. They’d always wondered what this was like. And after it turned out that yes, people do apparently walk in on you showering, Frisk felt like they were on a roll of discovery.

“It’s a little late for that, isnt it? I’m already here. And now I’m soaking wet, too, so I won’t be getting out anytime soon.” Asriel teased, bringing his hand over Frisk’s stomach and pulling them against him, making sure they were very much aware of how much their unintentional show had turned him on.

Feeling Asriel’s throbbing erection pushed against their back, Frisk bit into their lower lip gently. “Asri. Asri, come on. Don’t be like this.”

“Like what, Frisk? Turned on by my lover enjoying themselves? That hardly seems likely, don't you think?” Asriel laughed softly, turning Frisk around and pushing them up against the clean wall, holding their wrists to stop them from struggling. “And besides, I can’t leave your pretty little neck without bruises, can I? How will anyone know that you’re mine?”

Frisk paled a little, pulling futilely against Asriel’s superior strength. “What do you mean by that? I’m not your possession, Asriel.” Their tone was panicked, their expression moreso. “I don’t belong to you, at all. Get off!”

Asriel only tightened his grip, leaning in and kissing Frisk’s neck gently. “I know you aren’t a possession Frisk. But I won’t let anyone stare at you longingly anymore. Their jealousy o us, of what we are to each other. I won’t let it continue.”

As Asriel worked at their neck, licking and kissing and biting until Frisk could barely focus, the human shifted and writhed, their heart racing for all the wrong reasons. “Asriel. Get off of me right now.”

“And why would I do that, Frisk? When I have you exactly where I want you?” Asriel growled, digging his claws into Frisk’s wrists as he leant against them, holding them against the cold wall. “Why are you acting so hard to get all of a sudden?”

The caprine bit into Frisk’s neck, grinding his fangs into the tense, twitching flesh as he bucked his hips, grinding against Frisk’s stomach. Frisk panicked, desperately pulling at Asriel’s grip as they watched Asriel literally change in front of them, ornate black patterns appearing in his fur as they felt his fangs growing inside them.

Asriel pulled away, glaring dominantly at Frisk as he moved a clawed hand from Frisk’s wrist, instead tangling his fingers in their hair and forcing them to look at him. “Why so worried, Frisk?”

Frisk could barely speak. Their heart was racing and it felt as if something was very tightly gripping onto their lungs, breathing becoming a serious effort. “A-Asri, please. You aren’t yourself. Let me go. Please.”

Asriel smiled, an angry and unfitting smile to the goatmonster that Frisk loved. Frisk had never known how to cope with Asriel when he was in his Hyperdeath form, and they’d never seen it this close before.

“I’m not going to let you go Frisk. You belong to-” Asriel found himself cut off as Frisk punched him, hard, across the cheek. Stunned from the impact, he dropped them, stumbling back into the glass door of the shower.

Frisk felt like crying. Their heart ached, and it was all they could do to stop themselves from breaking down into tears. Short, ragged breaths escaped them as they leant weakly against the wall. “Why, Asri?”

Asriel pauses, silent for a while before sighing deeply and shaking his head, the markings on his fur slowly receding. “Frisk. Frisk, I am...I’m so sorry. I don’t know what happened.”

Frisk held themselves tightly, the water falling over them as they winced slightly, clawmarks in their wrists getting hit with the hot water. “You...you went Hyperdeath. Pinned me to the wall, wanted to...prove that I belonged to you. I thought-”

Frisk was silenced by Asriel hugging them tightly, so tightly that they could barely breathe as their arms were crushed against their chest. “I’m sorry. I just...I get so angry when people look at you, wanting you. Checking you out when we’re out together, it hurts.”

“Asri. I know you get annoyed with it. I don’t like when people look at you that way either. But you can’t just...you an’t try and own me. I’m a person, not an object.” Frisk pleaded, pushing away from Asriel and leaning away from him, as if worried he would change back at any moment.

“I know that Frisk! I just...I don’t understand it anymore than you.” Asriel sighed, reaching over and turning off the shower. “I guess I just lost control. I get so desperate to know that you won’t run off with someone else, that I just...” Asriel trails off, his voice cracking as he feels tears welling in his eyes. “I’m sorry. I’m sorry that I’m so possessive, Frisk.”

Frisk steps forward nervously, weakly wrapping their arms around Asriel, a shaky panicked hug being shared between the two. “We’ll figure it out, Asriel.”

Asriel swallowed hard, tightening his grip on Frisk as if worried they’d disappear. “I hope so. I’d hate to hurt you, Frisk. And...shit, I already have. Your wrists.” Asriel moves, grabbing Frisk’s arms carefully. “Frisk, I’m so sorry.”

Frisk winces, grunting slightly as their tender, sore arms are pulled, the wrenching pain causing the world to lose focus for a moment. “Ow, Asri. Be careful.” They smile slightly at Asriel’s embarrassment, knowing deep down that Asriel had not truly meant to hurt them.

“Sorry. But these look really sore, Frisk.” Asriel gently runs a padded finger over the small but deep-looking wounds in Frisk’s wrists where his claws had punched through the skin. “And I did this to you. I...I hurt you, Frisk.”

Frisk nods, a small smile on their face. “Yeah, you kind of did. But it’s alright, they aren’t big cuts. A good bandage and some painkillers will fix me up. Providing you didn’t want to tie me to the bed any time soon.”

The embarrassed silence that followed made Frisk blush heavily, even more so than the humid, sticky heat of the room was causing. “You were planning on tying me to the bed, weren’t you.”

“Only if you wanted to!” Asriel retorts, seemingly more embarrassed than Frisk. “W-wait, I mean no! N-not at all, where did you get that idea from?” Asriel coughs weakly, a nervous smile on his face, the pressure between the two seemingly forgotten.

Frisk laughs softly, pushing past Asriel and grabbing the towel they’d brought in for themselves, beginning to dry themselves. “You’re a pervert, Asri.”

“Really? You’re the one who wants to try SOUL sex and I’m the pervert?” Asriel chides, remaining in the shower so as not to drip water all over the bathroom floor. “That doesn’t seem right, does it?”

Frisk freezes in place, staring at Asriel wide-eyed. “What? W-w-what are you talking about, I didn’t even know-”

“Frisk. You forget that I’m made of magic. I just pried into your head a little while you were getting yourself off. Y’know, for ideas.” Asriel smiles, leaning against the wall as he winked at Frisk. “And what do I hear other than you almost begging for me to toy with your SOUL?”

“Shut up!” Frisk finally unfreezes, covering their face from embarrassment after throwing their towel at Asriel, hitting him in the chest. “I do not want you to do anything like that!”

“No?” Asriel begins to dry himself, stepping out of the shower as he does so, walking up to Frisk and leaning down to whisper into their ear. “So you’d turn it down if I offered? After all, with Mom and Dad working today, we could easily try it.”

Frisk sighed quietly. “Asri. You saw that I’m satisfied. I don’t think I could handle another round. I’m only human, I don’t have crazy stamina like you do.” Deep down, they wanted to experiment. To see what it would feel like, if nothing else. But they were tired, mentally and physically, from what had happened with Asriel only a few minutes before.

“It’s not...quite the same, Frisk. SOUL sex isn’t really...physical. It’s actually really quite hard to explain.” Asriel scratches the back of his neck, before taking Frisk’s hand in his and half-dragging them to the bedroom. “If you...if you want, I can show you instead.”

Noting Asriel’s sudden and intense nervousness, Frisk tilted their head a little in questioning. “What’s wrong, Asri? You seem really nervous all of a sudden.”

Asriel pauses, thinking over his words before replying. “This is a big undertaking, Frisk. SOUL sex isn’t like normal sex. It shows commitment, I guess. It’s pretty much the biggest show of trust and love for someone a monster can make. I’d be honored to commit such acts with you, but I’m also kind of scared that it might change you more.”

Frisk, assuming that was the case, simply approached Asriel and embraced the caprine as tightly as they could. “You’re scared I won’t be the same after it. But I’m stll going to be me, Asri. And, knowing that you’re this commited to me, I mean...you’re almost making it sound like SOUL sex is equivalent to, like, a marriage proposal or something. But surely it’s just another type of sex? Albeit a weird, and I guess more important one?”

Asriel shook his head slightly, carefully hugging Frisk back so not to hurt them. “It’s more important than you think it is, Frisk. In monster culture, it’s the ultimate show of commitment to another monster. Or, I guess human in our case. It’s how you tell someone you’re with that you want to be with them forever.”

Frisk locked up a little, their grip tighter and less comforting than before. “So it is like a marriage proposal. Asri, I didn’t know that. I was just being stupid and fantasising. I didn’t know there were implications behind it. Especially not ones that huge.”

Asriel deflated, pulling away from Frisk and looking to them, clearly trying desperately to hide how disappointed, or perhaps hurt he was. Frisk couldn’t really tell. “Then we won’t do it. It’s really just that simple. I just thought you should know what you were getting into before we did it.”

“Asri, it’s not like I don’t want to. But I’m human. Mostly. And that means I’m not gonna live very long compared to you. You’re a Boss Monster, so you’re guaranteed to outlive me.” Frisk reasoned, a sad smile on their face. “I don’t want to say forever because my forever is a lot shorter than yours.”

“Then become a monster, Frisk. You’ve already started. That way your forever will be just as long as mine.” Asriel pleaded, a desperation in his voice palpable enough to almost unnerve Frisk. “I love you, Frisk, and want to prove that. But lovebites and making out, and dating, it just isn’t enough. I was hoping that when we made love it would make everything okay. That I’d be happy like that. But I just...I don’t. The sex was great, but it was too...too normal, too mundane.”

Frisk pulls away from Asriel, stepping away from him. “So what, I’m not good enough for you as a human anymore? You’d only be happy if I gave you my SOUL, and became a monster? Unless I submit to you and...and belong to you, like you really want?” Their tone is angry, and more malicious than even Frisk themselves expected, causing Asriel to recoil slightly.

“Of course not, that’s not it at all Frisk! I don’t want to own you, I just want...more, I guess. What we have now is awesome, and I wouldn’t change it for anyone. But, yes. Yeah, I guess I would be happier if you were a monster. So that we’d be together for longer. So you could experience the world like I do, learning magic along the way. So we could be...more than we are. Not just siblings who are into each other, but a real, proper couple.”

Frisk felt ill. Hearing these things from Asriel, who Frisk had up until now been convinced loved them dearly, made their very SOUL hurt. It felt so very wrong to hear Asriel, their elder sibling and one of the most important people in their life, say such things to them. “So we aren’t a couple now. Is that what you’re saying? That I’m just some human you picked up because they were cute, because you wanted to see what you could do with them? We’ll only be a ‘real’ couple if I’m a monster too?”

“Of course not! Damnit, Frisk, why can’t you understand that I just want us to be happy together? It’s not that hard a concept.” Asriel’s voice shakes, desperation audible even to him. “I just want that, Frisk. I want to be happy with you, that’s all.”

“Just stop it, Asriel. I don’t even know how to process all this.” Frisk’s tone is harsh, their voice hoarse from stress as their stomach rolls and tightens, waves of nausea running through them. “First you change, then you try and beg me to become a monster so that you’ll be happier without even thinking about what I want.”

Asriel bows his head, tears pricking at his eyes as he nods weakly. “You’re right, I wasn’t thinking. I was just so desperate to prove my point that I’d do anything to make that happen. I just can’t bear the thought of you being anyone else’s.”

“I’m not anyone else’s, Asriel. You’re my boyfriend, nobody else. I love you but you’re acting in a really fucked up way.” Frisk’s throat, sore from the argument, burns in pain. “I thought this would make me happy, yknow? Having a partner, having you as that partner.”

“Aren’t you happy? Other than this argument, have you not been happy with me?” Asriel asks, wiping his eyes and sniffling quietly. “You always seemed happy. Embarrassed and annoyed a lot, but still happy.”

“I am happy, Asriel. But I just...this is so stupid, don’t you realise that? All of this is because I had a stupid fantasy about a stupid thing.” Frisk pulls at their hair, pacing slightly in a half-attempt to clear their mind.

“It’s not stupid, Frisk. You just didn’t get it, what SOUL sex means. We don’t have to do it, maybe ever. I promise I’ll do everything I can to get better. I don’t want to hurt you like this again.” Asriel looks into Frisk’s eyes, holding eye contact as he says so. “I don’t want to break up with you because I’m stupid and possessive.”

Frisk nods, a small smile on their face. “And I’ll do my best to make you happy too, Asriel.”

The caprine steps forward, tightly hugging his younger sibling. “I love you Frisk. Maybe a little too much, but I really do love you. I just wish I knew how to show it in a not creepy way.”

“We’ll work on it, Asri.” Frisk smiles, hugging Asriel tightly. They felt sore, and still damp, and they really weren’t sure of what to do with anything that had happened. But they’d managed to get through their fight with Asriel, and things had worked out, or seemed to have.

“Uh, Frisk? You realise we’re in our bedroom, naked, and hugging right?” Asriel asks, as if suddenly realising their situation.

“Yes, I’m aware. You aren’t suggesting what I think you are, are you?” Frisk asks, a weak smile on their face. If Asriel was after more than just hugging, they wouldn’t really mind. Honestly, the distraction would be welcome for them, after what had happened.

“I know it’s a stupid idea. But I thought it might help, since you seem to be even more stressed out than I am.” Asriel smiles nervously, genuinely believing that it would help both of them out, rather than any less pleasant motives. “Uh, but it would just be physical. No SOUL’s involved.”

Frisk smiles slightly. “Alright. But we need to take things slow, and carefully. I did just get off a few minutes ago. While you watched, you pervert.”

Asriel laughs quietly, picking Frisk up and climbing onto the bed, lying on the mattress with Frisk atop them. “I didn’t know you were in there, alright. And don’t say that like you wouldn’t watch me do it.”

“That isn’t the point, Asri.” Frisk pouts, pushing themselves up and straddling Asriel’s waist. “So why am I on top this time? I thought you liked being on top of me.” They shift their weight slightly, more to seek comfort than to arouse either of them.

Asriel smiles, gently stroking Frisk’s thigh. “It was nice, yeah. I guess I just wanted to see what it’s like underneath?” His smile turned a little nervous as he continued. “Y’know, we don’t actually have to do anything. We can just relax together.”

“Asri, relax. I don’t mind. I mean, I’m not exactly turned on right now but y’know.” Frisk shrugs, shivers running down their spine as Asriel’s claws gently trail over their thigh. “Be careful with those claws. I don’t want Mom to find scratches on me.”

Asriel laughs quietly, pushing himself up so Frisk was sat atop his lap, with them both now within kissing distance. Asriel leant forward, adopting the growling voice he knew Frisk loved. “That doesn’t mean I can’t scratch you though. Just not in places Mom can see.”

Frisk blushes, feeling a hot, burning sensation start to coil in their crotch as they tense up a little. They had really been hoping that Asriel wouldn’t guess at their scratching fetish so easily.

“Seems like you like that idea huh?” Asriel teases, biting gently into Frisk’s ear as he drags his claws slowly but more forcefully over Frisk’s tensed thigh, before moving both of his hands to Frisk’s back, moving his mouth to Frisk’s neck, dotting it in kisses and gentle bites.

Frisk swallows hard to stop themselves from drooling, their voice shaking as they speak up. “M-maybe we should fight more, if it makes you this loving.” They find themselves laughing nervously, the telltale heat in their loins getting more severe all the while.

Asriel smiles against Frisk’s neck, pushing his claws somewhat roughly into Frisk’s back, breaking the skin and causing the human to cry out, sounding half-pained. “I can be like this more often, if you want. I just thought you preferred when I was rough with you.”

Frisk panted a little, grinding their hips up against Asriel as they did so. “I like both. Just so long as you don’t go Hyperdeath on me while we have sex. I can’t think of anything that would ruin the mood faster.”

Asriel laughs hoarsely, continuing to slowly scratch Frisk as he worked at their neck, bruises already starting to show. “Fair point. But what happened to not being aroused, Frisk? It certainly doesn’t feel like that anymore.”

Frisk blushed intensely, well aware that they were now fully hard from Asriel’s ministrations. “Shut up Asri.”

“Not a chance.” Asriel replied with a soft laugh, clawing at Frisk’s back and maybe enjoying the sounds it brought out of them a little too much. “It’s far too much fun teasing you.”

“You’re a jerk.” Frisk groans, bucking up their hips against Asriel, their whole body aching with a surprising amount of arousal considering what they had done in the shower.

“I’m your jerk, Frisk.” Asriel says, pulling away from Frisk’s neck and kissing their forehead gently. “And every bit as turned on as you, by the way.”

Frisk smiled weakly, moving back ever-so-slightly and feelin how truthful Asriel was, the caprine’s needy erection now pushed up against their lower back. “Does that mean you want to...”

“I don’t have to go inside you.” Asriel says softly, pulling his clawed fingers free of Frisk’s back. “There are other things we can do. And not ones that involve our SOULs before you panic again.”

Frisk tilts their head in confusion. “There are other ways? I mean, I guess I’m pretty sheltered but I didn’t know. There’s, uh, what you did the first time. And the second time.”

“And more besides.” Asriel says with a wink, lifting Frisk suddenly and switching positions with them. “And hey look, now you get to be underneath me like you wanted.”

Frisk pouts slightly, moving to get comfortable and spreading their legs slightly. “So what are you planning, Asri?”

Asriel’s reply came in the way of motion rather than speech. Climbing over Frisk, the caprine pushed his hips forward, a hot friction grinding against his erection as it was pushed against Frisk’s own.

The human couldn’t stop themselves from letting out a rather erotic moan from the feeling, having Asriel’s larger member pushed up hard against theirs. Their whole body tensed as they instinctively wrapped their arms around Asriel’s neck. “I think I get it.”

Asriel laughs quietly, kissing Frisk softly as he slowly starts to rock his hips in rhythm, pushing up against his lover as they shared a kiss that felt almost desperate, trading bites before Frisk opens their mouth for Asriel, as had become normal for them. 

Asriel’s coiling tongue made its way into Frisk’s mouth as the human writhed beneath the caprine, bucking their hips into Asriel’s rhythm, the friction lessened by the copious amounts of precum dripping from both Asriel’s erection and their own. The hot, clinging stickiness that now covered Frisk’s stomach only made them more achingly aroused, the disturbing headrush given by Asriel’s tongue doing it’s best to asphyxiate them only making them more desperately needy.

The pair stay like that for many minutes before Asriel finally pulls his tongue free of Frisk’s mouth and throat, a hot trail of dark gray drool dripping onto Frisk’s chin and neck. The human gasps slightly for air, their chest heaving as raw, hoarse moans spill from them. “A-Asri. Asri, I’m so close.”

Asriel smiles, increasing the force of his thrusts against Frisk, his own erection throbbing to signal how close he was to his own orgasm. “Me too, Frisk. Do you want me to cover you again?”

Frisk nodded weakly, their whole body wracked with near-exhaustion as their lungs begged for the over-exertion to stop. The world span out of focus so Frisk closed their eyes, moaning loudly enough that they were convinced their neighbours must have heard them as their orgasm pulsed through them, hot strings of their cum hitting their stomach and chest. It felt warmer than normal, but Frisk put it down to simply being overstimulated.

Asriel grunts softly, the sight of Frisk being brought to orgasm causing his own to edge ever closer. “I g-guess something else changed about you huh?” Asriel lets out a soft, breathy laugh as they see that Frisk’s semen wasn’t as white as it used to be, now taking on a shade of gray more similar to his own.

Frisk opened their eyes, unable to even speak as they saw the coloring of the thick, gooey fluid that was strewn over them. They were barely capable of registering it, especially as Asriel’s heavy, clawed hand was suddenly placed over their neck, holding them down to the mattress. “A-Asri, what are you doing?”

Asriel smiles, his fangs bared as he pushes down gently on Frisk’s neck, more than aware of how much Frisk enjoyed having their air cut off. He hadn’t expected such a kink from Frisk, but was happy to oblige it.

Frisk’s eyes roll back a little, their still-hard cock twitching as they struggle slightly for air, grasping at the bedsheets as they feel Asriel thrusting hard and fast against them, a deep, growling moan escaping the caprine as he himself is brought to climax. Needing something to focus on, Frisk counts as over a dozen large ribbons of thick, searingly hot seed hit their chest and stomach.

As Asriel starts to come down from the rush of orgasm, he moves his hand off of Frisk’s neck, leaning down to kiss them gently on the forehead. “I love you Frisk.”

Frisk coughs weakly, a small smile on their face. “I love you too, Asri. But please ask me before choking me again.”

“I will.” Asriel smiles, his chest heaving as he breathes deeply. “I guess we should go and have another shower huh? Seeing as you’re all gray again.”

Frisk laughs quietly, nodding their head. “Yeah, I guess we should. At least we can’t fall asleep in there and get in trouble.”

The pair carefully climb off the bed, Frisk leaning against Asriel’s side. “I wish you wouldn’t make so much mess, Asri.”

“I can’t help it, Frisk. Monsters make a lot more mess than humans do.” Asriel replies with a smile. “Now come on, let’s go get a shower. And make sure those scratches aren’t too obvious. Unlike the bruises on your neck.”

“Goddamnit Asri, now I’m gonna get yelled at for doing stuff again!” Frisk groans, shaking their head. “I hope Mom punishes you too, you jerk.”

“We’ll have to see, won’t we.”


	7. Figuring some things out

**Notes for the Chapter:**

> Hey everyone, Aithe here. There's not a lot to say about this chapter, but I decided that I am going to go with the Monster!Frisk idea, especially as you guys seem to agree that's how things should go. Anyway, as always; feedback is greatly appreciated and I hope you enjoy!

Toriel’s reaction wasn’t as severe as either Frisk or Asriel had expected. Not that she hadn’t made Asriel feel very guilty for bruising Frisk’s neck; she just hadn’t been properly mad at them like the pair had both expected.

“Asriel, you know that Frisk is still recovering. While I am very grateful that you at least had the sense to protect Frisk’s SOUL this time, you shouldn’t have been doing such things with them while they aren’t at full health.” Toriel spoke softly, an unmistakable tone of disappointment to her voice.

“I know, Mom.” Asriel replies nervously, scratching at the back of his neck as he felt Frisk take his other hand. “I’ll wait until Frisk is fully healed before we do anything again.”

“I should hope so. I know you two disapprove of me being so aware of your sex life, but it’s for your own good. You are both my children after all.” Toriel smiles warmly, finding herself a little surprised at just how easily Frisk and Asriel had transitioned from siblings to lovers. She truly was happy that they both loved each other as truly as they clearly did, even if she wished she didn’t have to be so involved in their more...intimate connections.

“We know, Mom. But, if it helps, Frisk has been healing really well.” Asriel says with a small smile, holding Frisk’s hand tightly. “I know you said it would probably take weeks, but I really don’t think it’ll take more than a few more days at most.”

Frisk nods, glad that the dizziness that normally caused was completely absent this time around. “I’m feeling a lot better. I still get a little dizzy sometimes, but other than that I’m doing great. Asriel has been a big help, kinda.”

“I’m glad you’re healing, Frisk. But please remember that you must be very careful with Asriel. Because you are still human and he is not, there can be a lot of complications in how you two may want to continue your relationship.” Toriel leans forward slightly, resting her arms on the table in front of her.

“But, Mom, if I make sure to put up the protections around Frisk’s SOUL, won’t it be fine each time?” Asriel questions, suddenly feeling very unsure of himself. He had hoped that was the case but now felt very paranoid that it wasn’t.

“Honestly, I’m not sure. I’m no expert on it, but maybe Frisk can still change even with the protections. They are one of the most magic-infused humans that exists, after all.” Toriel says, unsure of how her children would react. “Taking precautions is needed, of course. But I would not be too surprised if, with you two as...energetic as you are, that Frisk may end up like us very soon.”

Frisk’s grip tightened on Asriel’s hand, the human paling slightly. “Like you? But, I still haven’t decided if I want to become more of a monster yet. I mean, I kind of have an idea for my choice but I’m still not sure.” They started to shake slightly, nerves making their legs feel weak beneath them.

Asriel held Frisk’s hand tightly. “That’s fine, Frisk. Then we can just...not have sex until you’ve decided.” Truth be told, he didn’t really like the idea of that but Frisk’s wants came foremost. After triggering his Hyperdeath transformation while the pair where showering, Asriel had decided that Frisk would always come first. He couldn’t bare to see them hurt that badly again, especially not because of him.

“That may be the best course of action, I’m afraid.” Toriel said, looking between the pair but mostly at Frisk, who was very visibly nervous. “I understand that those things are enjoyable but you may need to forego that pleasure until the decision has been made.”

Frisk swallowed, nodding their head weakly. “I guess so. I’m sorry, Asri, I just really want to make sure I know what I want before anything else happens to me, and my SOUL.” They let their hand slip from Asriel’s, resting them limply in their lap.

“It’s okay, Frisk. It’s a big decision to make after all.” Asriel replied kindly, nuzzling against Frisk’s cheek. “I’ll be here to support you no matter which one you pick.”

“As will I, my child. In fact, I think you would be a very handsome monster. Small, for a Boss Monster. But very handsome.” Toriel teased, relieved to see an embarrassed smile on her younger child’s expression.

“Thanks, Mom. I really needed to be reminded that I’m tiny compared to you and Asriel.” Frisk groaned, leaning slightly against his brother. “Maybe I’d get taller. And get horns too.”

“Maybe you would. You might even get proper fur instead of hair.” Asriel continued, wrapping an arm around Frisk’s shoulders and holding them tight to him. “You might just end up looking like a smaller version of me.”

Toriel laughs softly. “Please, Asriel, one of you is enough of an effort. Let’s not try to turn Frisk into another one of you.” She smiled widely at Asriel’s pout of mock-outrage, and moreso at Frisk’s laughter. She so rarely got to hear Frisk laugh anymore.

“It’s okay Mom. I’d be a much more handsome goat than Asri. Then maybe people would be jealous of you instead of me.” Frisk chided, yelping as Asriel retaliates by fluffing up their hair, causing loose strands to drop in front of their face and for their hairstyle to look much more like they had just gotten out of bed.

“Frisk, don’t tease your brother. And Asriel, don’t ruin Frisk’s hair. You know how hard they work on it.” Toriel says,, her motherly tone laced with enough authority to make even the most disobedient person do as she wanted. 

“Sorry, Mom.” The pair chimed nearly in unison.

“It is fine. I am glad to see the pair of you still getting along so well.” Toriel leans back into her chair, her hands rested in her lap. “I was worried that, with there being more than familial love between the two of you, that you may not be as close.”

Asriel raised an eyebrow, looking rather confused. “You did? But Mom, Frisk’s my best friend. Just because I make out with them a lot now doesn’t make me like them any less.”

Toriel glares at Asriel, who cowers slightly. “Please, Asriel, I already know far more than any mother should about the relationship their children are in. I would prefer to keep it at the already too-high level it is.”

Asriel nods slightly. “Uh, is that all then Mom?”

Toriel nods, her normal motherly smile back as it should be. “Yes, I cannot think of anything else I might need of you. Go and, as you called it, make out.” The elder goatmonster couldn’t help but laugh quietly to herself at the intense embarrassment clear on both Asriel and Frisk’s faces.

Still, that was exactly what they had planned on doing, so Asriel stood, helping Frisk up and walking with them out of the kitchen, through the living room and upstairs to their shared bedroom.

“Mom was right. She knows way more than she should.” Asriel says with a sigh, closing the door behind them both. “I never, ever want to talk to her about stuff like that again.”

“Agreed.” Frisk said with a nod, walking over to the bed and sitting on the edge of it. “Although it is your fault. If you just learnt to control yourself a little and didn’t leave my neck so colorful, maybe we wouldn’t have to talk to her.”

Asriel blushes, laughing nervously as he walks over to join Frisk on the bed. “I guess you’re right. And that time she found us in the bath really didn’t help. I didn’t realise it would stain you that badly.”

Now it was Frisk’s turn to blush, gently placing a hand on their stomach where, sure enough, their skin was still very lightly stained gray from their sessions with Asriel. “Maybe when we have sex again, you should...not get it all over me. M-My insides can’t be seen so staining them would be okay.” Frisk’s voice gets quieter throughout that sentence, so much so that Asriel can barely hear the whole of it.

“What was that, Frisk?” Asriel teases, pulling their younger sibling up and onto his lap. “Did I hear you right?”

“Asri, don’t make me say it again.” Frisk whines, shifting to get comfortable as they sit on their caprine lover’s lap. “I’m embarrassed enough.”

Asriel smiles, kissing Frisk on the forehead. “Fine, fine. I can hardly make out with you if you’re too embarrassed to kiss me, can I?”

Frisk nods. “Y-yeah, exactly. Uh, wait, we did come up here to make out? I thought you just wanted to escape the conversation.”

“I did. By coming up here and making out with you. I thought you were supposed to be clever, Frisk.” Asriel teases, a smirk on his face. “Now, shall we?”

Frisk nods, leaning into Asriel who meets them halfway. Frisk’s lips meet Asriel’s and the pair quickly settle into what has almost become routine for them now. With Frisk’s arms around Asriel’s neck and Asriel’s own around Frisk’s midriff, the caprine bites into his lover’s lower lip, the act he always used to signal that he wanted more.

Frisk complied, opening their mouth for Asriel, who quickly took advantage. Frisk had tried on numerous occasions to describe how it felt to have Asriel’s huge, inhuman tongue in their mouth, the heat and stickiness of his drool slathered over their tongue before the very distinct sensation of having his tongue push into their throat.

Frisk had always failed at trying to describe it. Mostly because every time they so much as thought about it, they ended up distracted by remembering. Now, however, with their eyes tightly closed and their breathing short and rough as Asriel toys with their tongue, his own pushing deeper into their throat than they could ever remember, Frisk’s mind was completely blank with pleasure.

Asriel adored having Frisk like this. There was something very carnal about having their mouth completely his, their tongue nothing but a plaything as his own was in their throat, the girth of his tongue causing their neck to bulge from it. And Asriel loved every moment of it, perhaps because this was something very possessive that Frisk thoroughly enjoyed.

The pair stayed locked like that for a few very long, breathless and, unfortunately for them both, incredibly arousing minutes, before Asriel slowly retracted his tongue, pulling himself away from Frisk and letting them breathe normally again. He smiled slightly at the dark blush on their cheeks, and the blissful expression on their face as they open their eyes.

“You’re getting a lot better at breathing while I do that.” Asriel says with a smile, his hands moving down to Frisk’s rear, adjusting them so they wouldn’t put any pressure on the tent in his pants.

“We’ve been doing it a lot. I had to get better.” Frisk laughs softly, breathing deeply as their lungs properly re-inflate. “Y’know I, uh, kinda...really like your tongue, Asri.”

“Oh?” Asriel smiles a little more lustfully, leaning back and resting on his hands. “And why is that, Frisk?”

Frisk swallows, knowing they won’t be able to just not answer the question. “It just feels really good, even when it shouldn't. Like, y'know, when its deep in my throat for instance. It’s a little addicting, I guess.”

Asriel leans forward again, half-whispering and half-growling into Frisk’s ear. “You know I could put my tongue in more places than your throat.” He knew he shouldn’t be saying it, especially considering the conversation they had just had, but Asriel was never, ever good at self-control.

Frisk didn’t care in the slightest that Asriel shouldn’t be teasing them. Hearing those intensely suggestive words made them shiver, a very quiet and shaky breath escaping them. “I’d love you to. But what if it changes me? It is still sex after all.”

Asriel moved back, looking rather sheepish. “I know, I just wanted to see how you’d react.” He admits with a nervous laugh. “It’s up to you, either way. Considering everything sexual we do might change your SOUL a little, I want you to be fully aware.”

Frisk pauses, looking pensive. “I, uh, I have been thinking about it. Remember I said to Mom that I kind of knew? I want to try it. Like, I know I can’t un-monster myself. But I’d like to get a little more monster in me. Don’t laugh. Don’t!” Frisk groans when Asriel is unable to resist laughing at the double meaning.

“Sorry, sorry. But if that’s really what you want, Frisk. Hm, but Mom is here. And you, well...you’ve been getting louder every single time. I don’t want her to hear because then she’ll come up and see what we’re doing and there is no way I am ever going to let her see us having sex.” Asriel shuddered a little at the thought of being caught in the act, especially by Toriel.

“I don’t think I’d ever live it down either. But how can I be made quieter? I can’t really help being loud.” Frisk laughs nervously, shivers of trepidation running through them. “We could wait until she goes out, I guess? Isn’t she supposed to be going out to meet Dad later?”

Asriel thought for a moment. “She was, but something came up at Dad’s work. Mom’s at home grading all day today.” It had been a good idea, but not one that would have worked. “If I wasn’t going to be pre-occupied, I’d cut your volume by holding your neck, seeing as you enjoyed that so much.”

Frisk blushes, curling up a little and feeling very embarrassed that they could now feel Asriel’s erection against them, their own pushing painfully against their pants. “I know I’m a pervert, okay. You don’t have to remind me.”

“Frisk. I’m trying to think of a good way to eat my brother out without our mother hearing. And you really think I’m not just as much a pervert?” Asriel laughs softly, kissing Frisk’s forehead. “That was what you assumed I’d be doing, right?”

Frisk tried to answer, only to find the words caught in their throat. They knew what that term meant, but the thought of having something as large, slick and prehensile as Asriel’s tongue inside them was somehow more exciting than the thought of Asriel penetrating them. Answering using a simple, weak nod, Frisk smiles nervously.

“Are you sure you’re okay with this, Frisk? You look nervous.” Asriel asks softly, concerned that he might be going too far too quickly. True, that was how this whole thing had started but now he was being more careful.

Frisk swallowed, nodding as they finally find their voice. “I am nervous. Your tongue is huge. And you can move it in a lot of ways. It’s hard not to be intimidated by the thought of having it in me.”

Asriel laughs quietly, pulling Frisk close and hugging them tightly. “I get it. I mean, I don't because I can’t do it to myself, but we’ll take it slow.”

“Thanks Asri.” Frisk whispered, breathing in Asriel’s scent to help calm them down. It was a weird thing that for some reason seemed to help more than most anything else.

“No problem, Frisk.” Asriel lifted Frisk off of his lap, lying them down on their back before climbing over them, kissing them briefly. “Now, let’s get these pants off of you so I can really get at you.”

Frisk nods weakly, helping Asriel as best they can as the caprine lifts Frisk’s hips, pulling their pants down and off, casting them aside. “I’m gonna lock the door then I’ll be right back.”

Frisk could barely answer, their breathing shallow and nervous as they hear Asriel’s footpaws across the floor, the air in the room feeling like a biting cold against their exposed legs, and especially their exposed and twitching erection. The click of the lock was nearly deafening to the nervous human, and they didn’t get any calmer as Asriel got to the bed again, climbing back onto it.

Asriel’s weight caused the bed to sink slightly, making Frisk tilt so that the caprine was in full view, lying between Frisk’s spread legs with a nervous expression. “Are you sure you want this Frisk? I know you’re hard, but I want to make sure.”

“Asri, will you stop teasing me?” Frisk groans, squirming and writhing, quickly throwing their hand in front of their mouth to muffle the yelp that came from them when Asriel lifted Frisk’s hips up, the human instinctively draping their legs over Asriel’s shoulders.

“Don’t say I didn’t warn you, okay?” Asriel says before holding Frisk against him, trailing his long tongue over their thigh and enjoying the half-muffled moans Frisk was making, a little too much. “I hope you’re gonna enjoy this, Frisk.”

“I-I’m sure I will.” Frisk barely even whispers, their nervousness now more on the possibility of them getting caught rather than what would happen. Not that that itself wasnt terrifying.

Frisk’s teeth dug hard into their hand, a desperate attempt to muffle the breathy, desperate moans that leaked from their mouth; as Asriel’s hot, clinging drool was pulled over their thighs, Asriel paying far too much attention to one of the few things Frisk didn’t like about themselves. “C-come on, Asri, I thought I said to stop teasing me!”

“I know, Frisk. But I love your thighs, and they deserve attention.” Asriel replied, causing Frisk to writhe and curse quietly as he peppered Frisk’s thighs with kisses and quick, gentle bites. “Don’t worry, I’ll still do what I planned.”

“You better, you huge jerk!” Frisk pants, squirming and writhing against the sheets, their hands eventually grasping Asriel’s horns.

The caprine swallows hard, a soft gasp escaping him as the sudden pressure was applied to his horns. “I get it, Frisk, you really want me to eat you out. So I’ll stop teasing you, alright?”

Before Frisk got a chance to reply in any way, Asriel’s tongue was dragged over Frisk’s entrance, a short but breathy moan escaping the human, who moved a hand from Asriel’s horn to keep themselves muffled.

Focusing intently on the task at hand, Asriel pulled Frisk more against him, grinding his hips against the bed as he moved his hands, pulling Frisk open as best he could in his position before delving his tongue into them, his own aching erection twitching violently as Frisk’s moans get more and more desperate and lustful.

The caprine pushes himself flush against Frisk, finding himself becoming slightly intoxicated by their smell. The scent of their arousal, the sensations of them convulsing and writhing because of what he was doing; it was all too much to bear as Asriel felt a familiar stickiness beginning to cling to the inside of his underwear.

Frisk felt like they may well pass out from the overwhelming, conflicting emotions they were dealing with. Thinking about what Asriel was doing was nearly enough to completely spoil the mood for them if they looked at it objectively, but the heat and the pressure of Asriel’s tongue pushing deep within them counteracted that, and then some. It was all Frisk could do to keep themselves as quiet as they could, the hand still around Asriel’s horn quickly being pulled free as Frisk grunted and moaned in pleasure, wrapping it tightly around their twitching, dripping erection. Thin trails and splatters of gray drew intricate patterns on Frisk’s crotch as they began carefully, rhythmically pumping themselves, a searing coil of tension boiling inside of them as their heart began racing. “F-fuck, Asri, I’m so close.”

Asriel smiled against Frisk, pushing his tongue deeper before stumbling upon Frisk’s prostate, pushing against it as he explored Frisk more. The sudden bucking of their hips combined with a full-volume moan from the human only made Asriel’s smile wider, grinding his tongue against the newly-discovered sensitive spot.

Frisk could barely keep themsleves muffled, and didn’t dare bite harder into their hand for fear of drawing blood. “Asri. A-Asriel, fuck me. Please, right now, just fuck me.” They hated begging, even more than they hated blushing. But seeing as the latter had become such a common occurrence, Frisk briefly worried that the former may soon be too.

It wasn’t an offer Asriel had expected, nor was it one that he was really going to refuse. Giving a particularly rough lick to Frisk’s prostate, Asriel pulled his tongue free, a dark gray staining clear around Frisk’s ass as Asriel climbed up and over Frisk, pushing their legs open wider. “Are you sure, Frisk?”

“Absolutely.” Frisk panted, their whole body slick with sweat. They let go of their erection, wrapping their arms around Asriel as they feel the now-familiar heat of their brother’s twitching, slick erection up against them. “I want you to fuck me. And I want to feel you cum inside me, Asri.”

Asriel smiled, moving and pinning Frisk to the bed by their throat, answering the unspoken but very loudly thought third request. “You really should remember I can read your mind when you’re this aroused, Frisky.” He teases, winking and digging his claws into Frisk’s neck, watching their eyes roll back a little as he thrusts his hips forward, feeling Frisk part around him due to the more than adequate lubrication his tongue had provided. Feeling Frisk’s pulse beneath his paw, and the heat of Frisk’s insides around his dripping hardon was already enough to push Asriel close to the brink, but he wanted to see just how far he could push Frisk.

Frisk themselves was in their favorite twisted heaven, having their air cut off by Asriel just enough to make them dizzy and the world to lose focus as they struggled for breath, their body wracked with pleasured convulsions as they writhed and bucked weakly underneath their lover, feeling his heat against them as the aching heat within them unraveled in the form of an orgasm strong enough that, if Asriel hadn’t been choking them, they were sure would have made Toriel more than adequately aware of what they were doing. Frisk counted ten streams of their seed hitting them, looking down as best they could; the novelty of the fluid now being a dark gray still not lost on them.

Seeing Frisk cum as suddenly and violently as they had spurred Asriel on, the caprine pushing in fast and none too gently. A single, clumsy slip of his weight forced Asriel far deeper into Frisk than he had intended, feeling them tighten almost painfully hard around them as Frisk cried out weakly, their voice strangled by the rough pressure Asriel had on their lovebite-covered neck. 

Feeling that he was nearly completely inside Frisk now, and that they seemed to have accepted them surprisingly well, Asriel kept that as the amount he could now push into. Fucking Frisk deeper and faster than before, Asriel winced as the bed started to creak slightly beneath the force of his thrusts before he held himself deep in Frisk, his tongue falling from his maw and dripping drool onto Frisk’s chest as Asriel’s own orgasm erupted, rope after rope after rope of his thick, clinging semen pouring into Frisk for the first time. 

Frisk couldn’t even come close to describing how it felt to have Asriel’s seed flowing into them. The heat alone was so severe that it almost felt like it was burning them, the pain it brought making their semi-hard cock twitch as if prepared to go again. Couple that with the throbbing and the panting and the sweat, and Frisk could have sworn that they could have cum again on the spot if they were potent enough.

Asriel stays deep inside Frisk for thirty more long, lustful seconds as the last of his seed was pushed into Frisk, before he slowly and carefully pulled himself free, his arms suddenly feeling very weak as he removes his paw from Frisk’s neck. “H-how was that for you?”

Frisk smiled weakly, pulling Asriel down and kissing him for a brief moment. “I don’t think I’ve ever had a more satisfying orgasm, Asri. I love you so much.” Frisk was nearly delirious with pleasure, their arms limp around Asriel’s neck.

Asriel smiled weakly, falling down beside Frisk and hugging them carefully, unsure of just how sore they may be after such a rough session. “I love you too, Frisk. You’re the best datefriend I could have ever asked for.”

“And you’re the best boyfriend I could have ever asked for, Asri.” Frisk said with a small smile on their face, their eyes half-lidded. They felt exhausted, sticky and more happy with themselves and Asriel than they ever had before. “I think I’m going to be happy as a monster if I can be with you.”

Asriel moves, his eyes wide as he looks to Frisk. “Frisk? I thought you said you weren’t sure?”

“I wasn’t. But, I guess now I am? I just...I want to be yours, Asri. Even if you get possessive, and paranoid, and overprotective. I feel really happy with you, and I want to keep being happy. As a Boss Monster.” Frisk’s reply is nervous, quiet and almost panicked.

Asriel brings Frisk close to him, hugging his lover tightly. “You have no idea how happy it makes me to hear that, Frisk. But we need to make sure, alright. If you still feel the same way in, like a week or so, then we’ll tell Mom.”

“That sounds like a good idea. But what sounds like a better idea is a nap.” Frisk says as they bury themselves in Asriel’s chest. “I’m gonna nap and then we’re gonna talk about it.”

“Sounds like a good idea, Frisk.” Asriel replies, yawning widely as he embraces Frisk tightly. 

The pair fall asleep not too long after, and around a half-hour later than that, Toriel tries to open the door to check on the pair. A quiet, frustrated sigh escapes the elder goatmonster as she finds it locked. “Asriel, you really need to learn how to control yourself around them.”


	8. Contemplation and Realisation

**Notes for the Chapter:**

> Hey everyone, Aithe here. Sorry for the slower update this time around, I was struggling to write this one. Fitting it into the story was pretty difficult, and I'm not sure how this one feels compared to the rest? I hope it's alright. 
> 
> Either way, as always I hope you guys enjoy and any feedback you have would be great!

“Mom, please don’t be mad at Asriel. It wasn’t him that started it, I swear.” Frisk stepped in front of Asriel as if it would do anything, staring up at Toriel who was visibly furious that her son had disobeyed her so easily and so soon.

“Frisk, I understand that you’re trying to defend him, but Asriel needs to be punished. It might not seem like it to you, but he is taking advantage of you.” Toriel’s voice is harsh, unlike what Frisk could ever have expected to hear from their normally calm and content mother.

Feeling Asriel cower away behind them, Frisk stands firm, fully ready to push Toriel away if they needed to. “Mom. I have always consented, or asked, for everything me and Asriel have ever done. The only advantage he’s ever taken is prying into my mind to find out what I’m too nervous to ask for.”

Toriel pauses, seething and balling her hands beside her. “I told you, both of you, that you were not to have sex until you decided. You honestly expect me to believe that you decided two minutes after going upstairs?”

Frisk tried to speak, but Asriel got there first. “No, they didn’t. It wasn’t an immediate thing, and I’m not going to be changing them for a while. Frisk made the decision that they want to be a Boss Monster by themselves, Mom. And we’re gonna wait to see if they still feel like that in a couple of weeks, give or take.” 

Frisk suddenly felt very insignificant, stood between the two far taller, more imposing goatmonsters. Their Determination was all that was keeping them going as they stepped back, grabbing Asriel’s hand and holding it tightly. “Asriel’s right, Mom. I decided this, he didn’t make me. I’m tired of sticking out in this family, being the only human. I want to really feel like part of this family, and really feel like Asriel wants to be with me. That’s why I’ve decided this.”

It wasn’t until Frisk felt Asriel’s hand fall from theirs and saw the nearly-heartbroken look on Toriel’s face that they realised exactly how much they had said. They were hoping that they could have been subtle about the reasons, perhaps making up something innocent.

“Frisk, is that true?” Asriel asked, his voice quiet and showing that he had clearly been hurt by what Frisk had said. Frisk watched as their brother walked away from them, standing beside Toriel as the pair looked at them, both visibly deeply upset by what Frisk had admitted. “You’re really only considering this for those reasons?”

Knowing that lying now and denying what was, inexorably, the truth; Frisk nodded weakly. “Yes, it is. I love you guys, I swear. It’s just hard to feel like a real part of the family. You two are goatmonsters, and Dad is a skeleton. And then there’s me, just...just a worthless human. I stick out, and I hate it. I thought that maybe, if I was a monster like all of you, that I wouldn’t get stared at as much, or insulted for being a half-breed.”

Their breathing shaky, Frisk swallows hard, their whole body shaking with panic as they find themselves unable to look at either Asriel or Toriel. “I never told either of you about it because I didn’t want you to worry that I was getting bullied. But there’s a lot of things I’m hoping will get better if I’m a monster. I’m not really excited about the whole idea, but I’m hoping it will make me happy.”

Frisk’s heart sinks and they could almost feel their SOUL shattering as they heard a quiet, choked sob from Toriel. They had always tried so hard to make it sound like life was going okay for them, but that was far from the truth. School had always been a nightmare, and Frisk knew full well the only reason that they had won Prom Monarch alongside the actually popular Asriel was because a lot of people voted for them as a joke, and it happened to backfire.

Asriel balled his fists, a complex mix of fury at the thought that anyone would have insulted or perhaps even gone so far as to hurt Frisk; and heartbreak that Frisk still couldn’t trust him enough to talk about things, even things as important as that. He felt his claws scratching roughly at his palms, trying not to show too much of how hurt he felt. “Frisk. Frisk, how could you?”

Frisk flinched at the sound of Asriel’s voice, stepping away from him on instinct as they bowed their head, swallowing hard and bracing for him to hit them. Their whole body felt tense but they couldn’t raise their head. They weren’t allowed, their years before falling into the Underground taught them that.

Toriel couldn’t take seeing Frisk or Asriel act the way they were, so she forced herself to speak up. “Asriel, stop. Something is clearly wrong with Frisk.” She could sense it even without having to pry into the young human’s mind. Their actions had been too fluid, too practiced for it to not be some kind of learned action from before they had fallen.

Asriel growled quietly, storming out of the room and leaving a very panicked Frisk and an even more concerned Toriel behind. Frisk slowly stood up straight again, rubbing at their eyes in a futile effort to stop themselves from crying. Their whole body shook, their legs feeling as if they may give out from underneath them at any point.

“I’m sorry, Mom. I promise I’m not trying to be such a disappointment.” Frisk speaks dejectedly, their arms hanging limply down at their sides. “I knew it would happen eventually. I guess it was stupid of me to think that I’d ever really get a chance to be happy.”

The harsh, self-hating laugh that spilt from Frisk’s mouth made Toriel’s SOUL ache. The human she loved most dearly in the entire world, her precious child, had been hiding so much and had been coping with so much trouble all by themselves. “Are you truly that unhappy, my child?”

It was a cowardly question; a way to desperately cling to the small hope that this was all some kind of twisted nightmare, and that her children were actually happy. It came as no surprise when Frisk weakly nodded, sniffling and wiping tears away from their reddened eyes.

“And you want to become a monster to escape it all, is that it? You hope that growing fur and horns, and perhaps learning magic, will make those problems go away?” Toriel asked, swallowing her nervousness. She knew she would have to be firm here, but knew moreso that she would hate doing so. She had always tried to be forgiving and kind, but sometimes it may not work.

“Well, I...I was kind of hoping so, Mom.” Frisk said quietly, still shaking with nerves and sadness. “I know it’s stupid. I can’t have all my problems disappear because I look different. I’m just hoping that it might help a little. Maybe people won’t think I’m a half-breed if I’m actually a proper monster.”

Toriel nodded sadly, walking up to her younger child and embracing them tightly. She wasn’t surprised when Frisk didn’t return the embrace, nor was it any surprise to the elderly caprine when she heard Frisk begin to cry against her. She gripped Frisk tighter, hanging her head sadly as she let them sob, feeling as if she may do so herself.

Frisk didn’t know how long they had cried for, but it felt far too long. Eventually pulling away from Toriel, they stepped back, wiping their eyes and looking down toward the floor. “I’m sorry. I shouldn’t have told you or Asriel anything. It would have been easier if you didn’t know.”

Toriel shakes her head. “That may be true, but it would not have been better. It hurts to know that you have been suffering, my child, but I am better off knowing it. And so is Asriel, even if he might not wish to admit it. Now, I think you should go and talk to him. We can talk about this more later if you wish.”

Frisk nodded weakly. “Yes Mom. Thank you Mom.” They cursed internally at how robotic they sounded before turning on their heel and leaving the room, hoping to find Asriel upstairs. It had sounded like he had gone up them, so Frisk slowly dragged themselves up onto the second floor of the house, knocking nervously on their bedroom door.

Frisk hadn’t expected an answer; so hearing movement behind the door and a rather disheveled Asriel looking down to them through a half-opened door was a surprise.

“What do you want, Frisk.” Asriel’s tone was quiet, but left no room for Frisk to doubt that he had no interest in speaking to them. 

Frisk shrunk away from the door, grasping at the bottom of their striped shirt. “I’m sorry, Asriel. I promise that I didn’t mean to hurt you.” The words sounded far less genuine than Frisk meant them as, so the human tensed up and braced in case Asriel would see fit to punish them.

“I know, Frisk. But you did, and badly. So right now, I want you to leave me alone before I do something I regret.” Asriel spoke as kindly as he could, seeing how intensely nervous Frisk was.

Frisk, hearing the unspoken threat that they assumed was there, paled and stepped back, apologising profusely before turning and nearly running down the stairs, panic flooding through them as they sat down on one of the couches in the living room, pulling their legs to their chest and hiding their face, tears stinging their eyes as they sob uncontrollably, fighting the nearly uncontrollable urge to RESET and fix all the problems they had caused.

It had been years since Frisk had even thought about the idea of a RESET. They weren’t even sure they were capable of that anymore. But they wanted to, so very badly. They wanted to fix what they had done, fix the pain they’d caused the only people who they could hope cared about them.

But they knew, deep down, that was wrong. Not that a RESET was a bad idea, but that it was wrong to believe anybody cared. All this happiness that they had was just an intricate charade, fake smiles to hide the lies and fake words to make themselves feel better.

They were too selfish to have anybody genuinely care, Frisk thought. Yes, breaking the barrier and freeing the monsters from the Underground had been good. But it wasn’t enough to mean that they deserved to be loved. They hadn’t been loved before they had fallen into the Underground and they saw no reason why that would change.

Frisk’s heart ached, their cheeks damp with their tears. This was all their fault. They should have shut up and never spoken about what they wanted, what they thought. Every time they were open about their desires it always went badly, like it had now.

This pain was too familiar to Frisk. The pain of believing that no matter what, they were the problem, that if they had just stayed quiet and done as they were told, and been a good child that nothing would have gone wrong. It was the pain that made them run away, that made them go to Mt. Ebott and cause this whole chain of events.

But they couldn’t run away this time. Mt. Ebott was empty now and they’d just starve to death down there, if they were even able to miraculously survive the fall a second time.

Frisk swallowed, shaking as they wipe tears from their eyes, holding themselves tightly. “I’m sorry, Mom, Asriel. I promise I didn’t mean to hurt everybody.” Their voice is quiet, and as broken as they felt. “I’m sorry for being so stupid and acting so selfish.”

Unable to even lift their head, Frisk allowed themselves to cry; the harsh sting of tears against their eyes as they sobbed uncontrollably, harsh and strangled breaths half-forced from their lungs as slow, agonising minutes pass. The crying only stops when Frisk’s lungs become too weak to continue, nearly unconscious from dizziness as their throat burned in agony.

They barely noticed when the couch sank beneath the weight of another, the warmth of a furred arm barely registering; they barely resist as they find themselves pulled into an embrace and find the voice that calls them muffled, as if not really there.

“Frisk, I’m sorry. I shouldn’t have freaked out at you.” Asriel does what he can to reassure Frisk, holding them tightly as he gently, carefully strokes their hair. He had never seen Frisk break down so completely, or seen them look or sound so heartbroken. He didn’t know what to do, or how to help. So he just held on to them, allowing them to recover on their own terms.

The pair stayed like that, Frisk near-inconsolable in their silence as Asriel hopes desperately that just being there for them is enough. He didn’t know what else he could do.

Neither knew how much time passed before Frisk finally felt strong enough to speak. Their voice was hoarse, and barely loud enough to carry to Asriel’s ears. “I’m sorry. Asri, I’m so, so sorry for what I did. I was so careless.”

“It’s fine, Frisk. I just wish that you’d told me the real reasons behind it.” Asriel did what he could to sound calm. This was only the second time that Asriel had felt his very SOUL struggling to hold itself together, the other being when he had been brought to the surface for the first time.

“I was scared. How do you tell your boyfriend that you don’t really know if they’ll love them if you stay a human?” Frisk struggles to speak, leaning weakly against Asriel. “I feel so awful for doubting you.”

“I understand, Frisk. I won’t lie to you and say that it’s alright, because it’s not. But I’m glad to see you understand what you did.” Asriel gently drags his fingers through Frisk’s hair, hoping that the small things he was able to do would help his younger sibling feel calmer.

“Asri, I...I won’t be upset if you want to stop being my partner. I screwed up really badly.” Frisk chokes on their words, not wanting to hear them. They didn’t want to face the consequences of their actions.

“That’s not how this works. I’m mad at you, yes. But I’m not going to stop being your partner just because of this.” Asriel reassures Frisk, surprised at how genuinely he meant it. Normally he was very impulsive and struggled with sensible, adult decisions but he knew this one was right.

“Really? But I said such stupid things.” Frisk didn’t know why Asriel would be so forgiving. It didn’t make any sense to them that something this severe could be ignored, or at least ignored to the degree it seemed to be.

“And you meant them. But we can work on it. We can be happy, Frisk, even if you find that hard to believe.” Asriel climbed over Frisk, straddling them and pulling them gently so that their eyes met. The caprine swallowed hard as he noticed very thin tendrils of black lacing Frisk’s sclera, knowing he’d have to mention that soon. “I promise, Frisk. We can make this work. Make us work.”

Frisk nods weakly, wiping at their eyes and smiling weakly. “I believe you, Asri. I-I love you okay. Please don’t ever forget that.”

“I won’t, Frisk. I promise.” Asriel smiles softly, kissing Frisk on the forehead. “Why don’t you go take a shower or something to relax?”

Frisk nods weakly. “That sounds like a good idea. Just as long as you don’t come and spy on me again.”

“I won’t, Frisk. You need the time to yourself.” Asriel nuzzles against Frisk’s cheek, before climbing off of them and helping them up. Watching as Frisk walks up the stairs again, Asriel gently places a hand over his chest, where his SOUL resides. Whispering to himself, Asriel grasped tightly at his fur. “I have to make this work. You deserve to be happy so much, Frisk.”

As Frisk disappeared from sight, Asriel walked through to the kitchen again, to find his mother who, thankfully, was still there. “Mom? Mom, can I talk to you real quick?”

Toriel jumps slightly at the sudden voice behind her, before turning to look to Asriel. “Of course, my child. This will be about Frisk, I assume?” When Asriel nodded, Toriel walked to the kitchen table, sitting down at it and gesturing for Asriel to sit opposite.

Obeying as he knew he should, Asriel takes his seat opposite his mother, his nerves causing his paws to shake and his eyes to dart around, desperate to focus on something but not being sure what.

“Now, Asriel. What is the problem? I assume that what Frisk said has shaken you, but I thought that you would be strong enough to cope with it in your own way.” Toriel’s voice was kind, helping slightly to relax Asriel’s racing heart.

“I’m trying, Mom. But Frisk doesn’t...he, sorry. They, they don’t believe that I love them because they’re a human. They want to become a monster to make me happy. I don’t know how to deal with that.” Asriel sighs, resting his head in his hands. His chest heaves with slow, counted breaths.

“I wish that I could help you, Asriel. But this is not a problem I can truly understand. Frisk’s decisions are their own, as are their reasons. We just have to trust that they believe in themselves enough.” Toriel places her hands on the table, inspecting Asriel; his nervousness and the deep-held panic that seemed to rest in his heart.

“They do. Of couse they do, it’s Frisk. They have far more Determination than pretty much every other human out there. But...I’m worried, Mom. About them. About us. I don’t want to lose them over this.” Asriel grips the edge of the table, wincing slightly at the force his grip enacts.

“I understand, Asriel. But you must trust them. If you don’t, then your relationship will never work out. If anything, you should speak to Frisk about this, when they feel calmer. Speak to them about your relationship. If they truly are only doing this for your benefit, then...perhaps you may be happier without the romantic connection.” Toriel’s voice was quiet, nervous even. She knew that Asriel was emotionally unstable right now, and that it would not take much for him to falter and lose his resolve, slipping into his Hyperdeath form.

“But I love them, Mom. I want to be with Frisk so bad that it hurts. I can’t just...I can’t not be with them, they have to be mine.” Asriel stands, the chair scraping along the floor as he starts to pace, pulling at parts of his fur. “Frisk is mine, Mom. Seeing other people look at them makes my skin crawl. It takes all the willpower I have not to just...hurt people who look at Frisk like they want them.”

Toriel leans back slightly, resting against the back of her chair. She stays silent, hoping that Asriel will continue even if what he has been saying is deeply unnerving to her.

“I can’t help it, Mom. I just...I need Frisk. I need them to be mine because giving them to someone else isn’t...it isn’t right. Frisk is mine.” Asriel finds himself nearly delirious, a trancelike state overcoming him as he paces across the kitchen floor.

Toriel, hearing the venom and desperation practically dripping from Asriel’s voice, stands from her own chair, walking to her child and placing her hand on his shoulder, her grip tight enough to stop Asriel in his tracks. “Asriel. Frisk is not your possession. Yes, I understand that you love them dearly. But you don’t own them. They aren’t your pet, or your slave. They’re your sibling.”

Asriel shifts, trying to pull away from Toriel’s grip. “I know that. But that doesn’t make it better. That doesn’t mean people can look at Frisk like that. Do you have any idea how badly I want to hurt people that do that, Mom?”

“No, Asriel, I don’t. Because I am not possessive like you are. You need to work on this, Asriel, or else you will ruin your relationship with Frisk; romantic and otherwise.” Toriel scolds, her grip tightening to keep Asriel in place.

“I don’t have to work on a damned thing! Frisk belongs to me, not to anybody else!” Asriel pulls free of Toriel’s grip with a strength only begotten to him when he was in his Hyperdeath form. And, sure enough, the ornate black markings started curling around Asriel’s body, his horns lengthening as he grunts, panting slightly at the pain that the physical parts of his transformation overcame him.

“Frisk is mine, mother. Not yours, not Dad’s, not anybody elses out there. Frisk is my partner. My lover. Frisk is mine, and nobody is allowed to take them from me.” Asriel growls, thick strings of his stone-gray drool falling from his slathering maw onto his chest. “Why does nobody understand this?”

Toriel steps back, doing everything she can to hold her shaky resolve. She knew she was nowhere near strong enough to subdue Asriel physically or magically. She just had to calm him down somehow. “Asriel, please; think of Frisk. Frisk’s emotions are every bit as important as yours in your relationship. Would you discard their feelings so easily?”

Asriel scratches at his paws, digging lines into his palms as he stares Toriel down, his back hunched from the unbalanced weight he had in this form. “Frisk knows that I’m right. They wouldn’t turn me down, they love me. They’re doing all of this for me and you honestly believe that Frisk’s feelings are any different from mine?”

“I do not believe that Frisk wishes to be your slave, Asriel. Yes, they love you. But you are not sounding like you truly love them. You simply want to own them, to make them yours so you can hold them on a pedestal.” Toriel stands tall, her back as straight as she can make it as she does everything in her significant power to make herself the dominant will. “You are trying to show others that they are yours, so that they cannot have them.”

“Bullshit!” Asriel spits, dragging his footpaw back and leaving gouges in the kitchen tile, a vicious high-pitched scraping noise echoing through the house. “Frisk isn’t a goddamned possession, they’re my lover! Mine! That’s what nobody understands! No matter how much I bruise their neck, or stain their skin, or anything else, people always stare. People always stare, and they’re always so fucking lustful. I don’t need to see into their minds to know the filth that runs in their heads, all of it always about Frisk. My Frisk.”

Toriel sighs deeply, walking up to Asriel and wrapping her arms tightly around her son’s chest, a tight grip holding her there as he growls and shifts, trying to pull away from her. “You’re just scared, aren’t you? Beneath all of this anger and violence, you’re just scared Frisk doesn’t love you.”

“That isnt it!” Asriel curses, furious that he finds himself unable to release himself from his mother’s vice-like grip. “Frisk would never abandon me!”

“You know that. But you keep having to repeat it in case it isn’t true all of a sudden. I understand how you feel, Asriel. You need to talk with Frisk about this.” Toriel says, a soft smile on her face as she stands back from Asriel, a desperately pained expression on the younger caprine’s face.

“I can’t, Mom. Frisk is broken, and is thinking about a RESET. I can’t bring this up. None of this.” Asriel growls, his voice shifting as he stands more upright, the black designs on his fur slowly unraveling and receding, fading from his body entirely shortly after. “I’m sorry, Mom.”

Toriel smiles softly. “You needn’t apologise, my child. You are simply panicking and do not know how to resolve the issue. Many people, monsters and humans alike, have been in situations similar to yours.”

“I just want Frisk to be happy Mom.” Asriel sighs, wincing as he pulls his claws free of his palms. “They’ve put up with so much crap that I just want them to be able to forget all of that. I want them to be happy, with me. And in general.”

“I know, Asriel. Now go. Go and find Frisk, and talk to them. If you two don’t work this out, both of you will be struggling to be around each other for a long time. And considering you sleep together, that seems unwise.” Toriel smirks a little, turning Asriel around and pushing him lightly.

“Got it, Mom. Thanks, really. I don’t know what I’d do without you.” Asriel smiles to himself, not unsurprised to hear no reply from Toriel as he walked through the living room once again, making his way up the stairs to the bathroom. Hearing the water still flowing, Asriel decides this time that knocking would most likely stop him from making everything worse.

Frisk jumps at the sound of the loud knocking on the door. Leaning against the tiled wall to stop themselves from slipping, they breathe deeply before calling out. Hearing that Asriel is on the other side, Frisk allows them in. Glad that the room is full of steam and that they themselves are entirely shameless and thus don’t care about Asriel seeing them; Frisk turns to face Asriel, trying not to look as nervous as they felt.

“I thought I told you not to come and spy on me, Asri.” Frisk does what they can to play it off, hoping desperately that Asriel couldn’t tell how badly their hands were shaking.

“I’m not here to spy on you. I just didn’t want to wait to apologise to you, Frisk. I need to...to really apologise.” Asriel leans against the wall, tense and intensely nervous. “I’ve been...really screwing up. Like, a lot. I’ve been so busy trying to make you happy that I didn’t think about...about what would actually do that.”

Frisk tilts their head a little in confusion, turning the shower off and opening the shower door once the water had stopped flowing, leaning back against the cold glass as they look to Asriel proper. “Asri. If either of us need to apologise, it’s me.”

Asriel stands, stepping up to Frisk and placing a hand on their shoulder. “Frisk, don’t. We both know that both of us have fucked up a lot recently. I was too focused on making this work, but hadn’t asked you how that would happen. I just...I wanted, no. No I kind of still want to own you. Like, not as a pet or anything but it’s...it’s complicated.”

Frisk frowns a little, confusion mixed with worry on their expression as they shift their weight. “Asriel. Listen to me, alright? I really, honestly don’t mind that you’re so possessive. I mean, yeah, it’s kind of weird. But I don’t care.”

Asriel raises an eyebrow, confused. “What? Frisk, that’s....stupid. Of course it’s stupid, all of this is stupid. I’m dating and screwing my younger sibling and all of this fighting is because they’re trying to change their species.” The caprine finds himself laughing quietly, rubbing the back of his head.

“Yeah. Yeah, this is stupid, Asri. Not the relationship; our relationship is awesome but this is real stupid. We shouldn’t be fighting over me wanting to get fur and horns and stuff.” Frisk sighs, stepping closer to Asriel and wrapping their arms around him, holding him in a tight hug, not caring at all that they were naked.

“We’re gonna be able to move past this, right Frisk? We can be happy.” Asriel returns the embrace carefully, gently toying with Frisk’s hair. “I mean, once we get past all this stupid emotional crap, it’s all gonna be great.”

Frisk nods, nuzzling into Asriel’s chest and wincing a little at how his fur stuck to their wet skin. “I really want it to be good. Us, to be good. That’s one of the reasons I want to be a monster.”

“Do you have any reasons that aren’t to do with shitty people, or me?” Asriel questions, curling Frisk’s two-tone hair around his fingers. “I’m hoping you want to do this for yourself, too.”

“I do. Ever since I first saw Mom, I wondered what it would be like to be one of you guys. Y’know, all of you are so tall and so...so attractive that it’s really unfair. I just always kind of wanted that for myself, I guess.” Frisk admits quietly, a hot rush running through their body from the embarrassment of such a childish admission.

“Wait, did you just call Mom attractive?” Asriel questions, well aware of the real meaning behind what Frisk had said but immediately having some kind of very unusual annoyance at hearing what he assumed he was hearing.

“Yeah? I mean, I know she’s my Mom. But she’s still really hot. Y’know, all tall and curvy and-” Frisk pauses, biting their lip as the realise exactly what they’d said. “I didn’t say anything. Not one word of that sentence happened.”

“You had a crush on Mom, didnt you Frisk.” Asriel’s voice is quiet as he tries desperately to hold back laughter at Frisk’s intense embarrassment and how they kept tripping over their own words. “Back in the Underground?”

“No! Not at all! W-why would I ever have a crush on a really tall, really pretty woman who just happened to be incredibly caring?” Frisk half-laughs nervously, stepping away from Asriel and looking away to hide their embarrassment. “That’d be stupid, Asri. Don’t be stupid.”

“Frisk, pretty much everyone who’s met Mom had a crush on her at some point.” Asriel admits, leaning back against the wall again, smiling a little at his younger sibling’s annoyance and embarrassment. “But, y’know, none of the ones who crushed on Mom ended up screwing her son. Other than you.”

“Asri, stop!” Frisk groans, pulling at their hair as trails of water drip from it onto the floor. “You’re such an asshole, you know that?”

Asriel laughs softly, shrugging a little. “I guess I am, Frisk. But I’m glad to see you happy again. Even if I have to be a jerk to you to do it, seeing you smile is good.” The caprine smiles widely, his fangs bared as he looks at Frisk, who finally looks back to him, their own smile smaller and more embarrassed, but definitely there.

“Thanks, Asri. I know we both kinda wimped out on apologising, but...thanks. I really appreciate all you’ve done for me, and how you’re willing to put up with all the crap I give you.” Frisk rubs their arm, unsure of what to do with themselves as they blink a few times, shaking their head as a short spell of dizziness overcomes them.

Asriel steps forward, catching Frisk as they nearly slip and stumble, his claws instinctively digging into them, causing them to hiss quietly, glaring at Asriel. The caprine swallows hard as he looks back into Frisk’s eyes, seeing them now nearly perfectly mirroring his own, Frisk’s sclera now a gray so dark that it was nearly black, their irises a stark white in contrast to it.

“What are you looking at me like that for, Asri? I just got a little dizzy.” Frisk stands with Asriel’s help, feeling a little uncomfortable under Asriel’s very intense gaze. “I don’t think I got soap in my eyes or anything, did I?”

Asriel shakes his head, stepping back. “No, no you didn’t. Frisk, I....don’t really know how to sugar-coat this. Your eyes have...your eyes look like mine. All dark and stuff.” Asriel finds himself stumbling a little on his words, entranced by the new, albeit very sudden change in Frisk’s eyes.

“They do? Like, all of a sudden?” Frisk looks a little shocked, but not overly surprised. “I guess all these changes are gonna happen out of nowhere, huh?” The human shrugs nonchalantly, taking their towel from where they had left it, wrapping it around their waist and holding it in place.

“You seem awfully casual about having your eyes get all screwed up out of nowhere.” Asriel comments, following Frisk as they walk through to their shared bedroom. “I guess you’re looking forward to becoming a monster, huh?”

“Of course I am, Asri. I get to be all furry and soft, and I might get sweet horns and stuff. I might even get magic!” Frisk’s eyes shine a little as the pair enter their bedroom, Asriel closing the door behind them, listening intently as Frisk continues listing all of the possible outcomes that had them excited.

It made Asriel realise that maybe this wasn’t a bad idea after all, having Frisk be a monster like them. Maybe it would make Frisk eveery bit as happy as he knew it would make him. This wasn’t the commitment that Asriel had hoped for, but it was enough. It was something very solid and very important.

It was hard, factual proof that Frisk loved him as much as he loved them.


	9. Falling Apart

**Notes for the Chapter:**

> Hey everyone, Aithe here. Sorry for another slow update, I've not been feeling too great recently so my ability to write pretty much went out the window until I recovered. 
> 
> But, I am now better and have finished this chapter. I just hope you guys don't hate me for this one.

“So you have truly settled on this, then?” Toriel asks, a worried expression on her face as she looks over the table to her children, a small part of her realising that all of the important conversations she seemed to share happened over this table.

Frisk nodded, their hand reaching for Asriel’s beneath the table. Finding solace in his grip, Frisk looked between Toriel and Sans, both of whom were sat opposite them. They hadn’t been able to keep their decision a secret, but now that it had been told; Frisk found themselves exceptionally nervous.

The silence was palpable as the elder monsters observe their children, as if silently waiting for them to change their mind and leave. Agonisingly long seconds pass before Sans finally speaks up, breaking the tension with his words. “If you think you’ll be happy as one of us, kid, I’m all for it. But, you do know it’ll suck right?”

Frisk nods, holding Asriel’s paw tighter beneath the table. “I don’t expect changing to be easy. But I want to do it. I want to live my life as a monster now.”

Asriel spoke up as Frisk fell silent, gently stroking the human’s palm. “I’ll be helping them through it, too. As it’s up to me to trigger all the changes, I’ll be doing everything I can to help.”

Sans leans forward, his normally cheerful grin seeming worryingly serious. “Asriel, I’m gonna be real with you. These changes you’re gonna be putting Frisk through? They aren’t gonna be pretty. Their skeleton will be re-arranging, their skin will be growing fur that it’s not normally meant to have. It’s going to make both of you suffer. A lot.”

Frisk swallowed hard, curling up on themselves a little. They knew that changing would be rough, but hadn’t truly considered how severe the changes would really be, or at least while changing. The warmth of Asriel’s paw felt worthless now, with the panic that was beginning to form in their chest.

“We’ll get through it. And if Frisk can’t cope, we’ll stop until they can. You need to trust us.” Asriel’s voice was firm, as was his grip on Frisk’s shaking hand. He knew they’d be alright, given time. “This isn’t a decision Frisk or I have made lightly.”

Frisk nods, doing everything they can to stop themselves from shaking. “I-it’s scary to think about how much the changes are going to hurt. But I want to have them, Dad.”

Sans leans back again, shrugging as he looks between the two. “Well, you can’t say I didn’t warn you.”

Toriel sighs quietly. “As much as I hate to admit it, your father is right. The process will be long and difficult. But I believe in you both. I’m sure that you’ll be able to get through it; and of course it should go without saying that Sans and I will help you wherever we can.”

Frisk’s heart settled a little at hearing that, and moreso when Sans nodded, the sinister aura around him having faded. They were still nervous, the harsh reality of how unpleasant the changes would truly be finally hitting them.

“And before you start assuming that all of these changes are going to mean that you and Asriel will be constantly...I’ll put it politely and say ‘enjoying each other’ in your bedroom, that isn’t how this will be working. Yes, granted this means that now Asriel will not need to protect your SOUL when you have sex, but many if not most of the serious changes will need to be triggered in encounters.” Toriel explained, her tone serious and authoritative as she went through the details.

“Mom, I...I know we need to talk about this, but can we go through the exact details closer to when we actually need to trigger the changes?” Frisk balls their free hand tightly, desperately hoping that their interruption wasn’t going to be an issue. “I’m already starting to feel overwhelmed with all of this information.”

Toriel pauses, frowning slightly but nodding. “I understand, Frisk. I’m sorry for causing you stress.” The elder caprine stands from her chair, brushing her clothes down. “But do not hesitate to ask me questions since I’m sure there will be some.”

Frisk nods, standing shakily and leaning against Asriel as he stands beside them. “I will do, Mom. I think I need to go...think about stuff. All of this is so confusing that I need to try and clear my head a little.”

“Should we go for a walk, Frisk?” Asriel offers quietly, walking with his younger sibling out of the kitchen, closing the door and hearing muffled voices behind it mere moments later. “It might help clear your head, and you haven’t been outside for a week or two now.”

Frisk nods weakly. “The fresh air might do me some good. I guess we should probably do the rounds in town, and find all our friends from school? I mean, nobody knows we’re dating so we should tell them.”

Asriel smiles, leading Frisk through the living room. “You do remember that I dipped you beneath a spotlight at prom, right? I’m pretty sure everyone knows we’re dating.”

“Asri, everyone kisses their date at prom. And I don’t think it looked weird, most people just thought you were being dramatic. Y’know, like you always are?” Frisk teases, stepping away from Asriel and walking in front of him up the stairs, walking to the closet once they entered the bedroom and looking through what was inside.

“I’m not that dramatic, Frisk. I’ve grown up a lot since my “Absolute God of Hyperdeath” days.” Asriel pouts, joining Frisk at the closet and just pulling out whatever was closest and his. Walking over to their shared bed, Asriel sits upon it and observes Frisk as they pick through the clothes.

“You’re still a drama queen, Asri.” Frisk replies, pulling a shirt from the closet and holding it in front of them. “What do you think? Is this one too big?”

Asriel smiles, his fangs just bared. “Considering it’s my shirt, yeah it’s too big. But go ahead and wear it if you want.” The caprine can’t resist laughing softly at the resulting embarrassment from Frisk. “I’m serious, it’ll look cute on you.”

“I don’t want to be cute!” Frisk pouts, crossing their arms in front of their chest. “Damnit, Asriel, why do you always need to be such a jerk? I just want to pick a shirt but no, you have to embarrass me and point out that I’m dumb.”

“Frisk, relax alright?” Asriel stands, leaving the clothes on the covers. “Listen, I know you’re stressed out about all this but it’s going to be okay.”

“What if it’s not, Asri? What if one of the changes goes wrong, or the encounter goes awry and I get injured?” Frisk turns on their heel, throwing the shirt aside. “What if I make a stupid decision and end up hurt, or worse?!” Their whole body starts to shake, their now-inhuman eyes glistening with tears.

Asriel wraps his arms around the shivering Frisk, holding them closely to keep them from moving too much. “It won’t happen. I promise I’ll keep you safe, Frisk.”

“What if you can’t, Asriel. What if when you’re trying to change me, something goes wrong and I get badly hurt? What if a change goes wrong and I’m in pain for the rest of my life?” Frisk chokes on their words, resting their forehead against Asriel’s chest. “I’m scared, Asri. I’m really scared that I’m making a terrible mistake.”

“You can still change your mind, y’know. We can leave the changes at two-colored hair and inverse eyes.” Asriel reminds Frisk softly, running his hand through their hair. “The choice is entirely yours.”

“I know. I know, but I can’t be a coward. I have to go through with this, it’s better this way.” Frisk pulls free of Asriel’s grip, wiping their eyes and smiling sadly. “I might finally feel happy as a monster, Asri. I can’t let being scared get in the way of that.”

Asriel chokes back his reply, his cheerful expression falling to a much more solemn one. “Frisk, who are you really doing this for?” He pushes his hands into his pockets, looking deeply into Frisk, who cowers slightly from his gaze.

“What do you mean by that?” Frisk questions nervously, a noticable voice crack as they do so. “Asri, why are you making such a big deal out of why? Can’t you just accept it?”

“No, Frisk, I can’t. You’re making it sound like you’re doing this for reasons that don’t make any sense. I want to know the real reasons behind it all.” Asriel pries further, stepping toward Frisk, who steps back as he does so.

The human whimpers quietly, stumbling and falling back as they land on their rear, looking up with panic in their eyes toward their caprine sibling. “I’m sorry, I’m sorry. Asriel, please, I’m sorry.”

The fear in Frisk’s voice pulled at Asriel’s SOUL. He had no idea what he had done to trigger such instant and severe panic in Frisk, but knew it must have something to do with the past that they had never shared.

Frisk shifted back until their back hit the wall, where they pulled their knees to their chest and held themselves, fighting back tears. This was all wrong, this decision was supposed to help but they were caring too much and thinking too much and it was ruining everything.

Asriel felt powerless to help. Rooted to the spot for some reason he couldn’t understand, all he could do was watch as Frisk curled themselves up in the corner, hiding away as if he had threatened them with something awful; when all he had wanted were reasons. This wasn’t the first time he had seen Frisk so completely afraid, but it was happening too often now.

A few long, painful moments pass before Frisk finally looks up, worrying Asriel with how confused and upset they looked. “W-why haven’t you pulled me up, Asri? I-I fought back, and ran away, a-and you haven’t pulled me to my feet, or smacked me, or anything. I don’t understand.”

Asriel couldn’t take hearing how entirely broken Frisk sounded. Even before, when he had found them crying on the couch by themselves,they hadn’t sounded this dejected. Half-running to Frisk’s side, he sat beside them and hugged them as tightly as he could, his SOUL threatening to shatter at the panicked, desperate sobbing that came from Frisk only moments after he did so.

“I’m never going to hurt you like that, Frisk. Nothing you could ever do would make me want to hurt you, or make you suffer.” Asriel’s voice is soft, and he hoped it sounded as caring as he meant it to be. “I promise that I’ll do everything I can to keep you safe.”

“But you’re supposed to hurt me, Asriel. This is the real world now, not the monster’s world.” Frisk stumbles on their words, their throat sore from crying. “I can’t expect Mercy here. I make mistakes and they get punished.”

Asriel gently began to toy with Frisk’s hair, feeling more and more worried every moment that Frisk stayed like this, nervous and small and panicking. “Not by me, they won’t. Please, Frisk, try to understand that I’m not here to hurt you.”

“But why? Why don’t any of you ever hurt me?” Frisk whimpers, leaning weakly against Asriel’s warmth, taing small solace in his body heat. “I’m always such a screw-up, and I can’t do anything worthwhile and...and I’m not even a monster, yet Mom and you, a-and Dad...you always act so nice. I just can’t understand.”

“You don’t have to understand, Frisk. A lot of things don’t make much sense, and family is one of them.” Asriel speaks kindly, nuzzling against Frisk softly. “That’s what we are, Frisk. Family.”

Frisk nods weakly, pulling away slightly and looking up to Asriel. “Yeah. Sorry for freaking out so easily Asri.”

“You don’t need to apologise, Frisk. Everyone is allowed to be fragile at times. But you’re so much stronger than this, and we’re gonna get through these troubles together.” Asriel leans forward, kissing Frisk’s forehead gently. “I promise.”

Frisk nods, wiping their eyes. “Yeah. Yeah,I believe you. I think we can get through this. I’ll try to be brave, for you. And for Mom and Dad too.”

“That sounds good to me. Now, lets clean you up and go for that walk, alright? You could certainly do with the fresh air after all this.” Asriel smiles, pulling Frisk to their feet and helping them as they stumble slightly, unbalanced. 

“Thanks. Who do you think we should go see? Or should we just take a walk?” Frisk asks, walking over toward the discarded shirt from before and picking it up, holding it to their chest.

“I think we’ll just go for a walk. We might find someone on the way, anyway.” Asriel replies as he walks back toward the bed, stripping off the t-shirt that he had worn to bed the night before as he does so.

Frisk struggles not to stare at the muscles clearly visible beneath Asriel’s fur; as they take off their own top. Looking down, Frisk frowns slightly at the significantly less muscular body that they had. It wasn’t that they were unfit, far from it. But they weren’t built the same as Asriel and it annoyed Frisk somewhat.

Sighing quietly as they put on the shirt Asriel allowed them to borrow, Frisk looked toward Asriel again, waiting for him. They couldn’t help but swallow hard as Asriel turned to them, still shirtless. Frisk cursed internally at how easily they were flustered by Asriel’s appearance.

“Something wrong Frisk? You look embarrassed.” Asriel teases, smirking at Frisk as he flexes slightly, making the human blush and look away. “You just recover from stressing out and already start staring at me?”

“S-shut up, Asri. Maybe it helps me calm down by looking at how hot you are.” Frisk retorts, annoyed as they glare at Asriel and how smug he looked.

“Maybe it does. But before you start trying to act on all those dirty thoughts running around in your head, we should get you outdoors. Clear your head of all that.” Asriel pokes out his tongue, only worsening Frisk’s embarrassment.

“Asri! Don’t just pry into my head like that, that’s not cool! A-and I’m not thinking dirty stuff!” Frisk flusters, pulling at the hem of the shirt they’d just put on. Of course, Frisk knew perfectly well that they were lying but they wouldn’t be caught without defending themselves.

Asriel simply laughs, pulling his new t-shirt up and over his head, taking care not to catch it on his horns as he pulls it down, fitting it over himself. “If you say so Frisk. And I wasn’t prying in your head. I just know you very well.”

Frisk paused for a brief moment before letting out an outraged groan, balling their fists. “You’re the worst kind of asshole sometimes, Asriel. You’re lucky you’re so goddamned perfect in other ways.”

“I love you too, Frisk.” Asriel replies with a smile, walking up to his smaller sibling and ruffling their hair. “Now come on. I know a nice quiet route we can take our walk on. With some secluded areas too, in case I decide to indulge you a little.”

Frisk’s reply catches in their throat, replaced with a quiet, embarrassed whimper as they nod weakly, following Asriel down the stairs. Nodding as Asriel informs them that he’s going to tell their parents about their walk, Frisk sits upon the stairs, taking a pair of their shoes from nearby and pulling them on. 

There was a large part of Frisk that was still completely unsure of how to cope with their situation. Despite having lived with their adopted family for years now, it wasn’t until the past few days that they had finally wondered if this was what family was really meant to feel like.

They weren’t sure they liked it, either. Feeling wanted was unsettling, a pressure that they didnt want to have to deal with. But, at the same time, it made them happy in a way. They’d never really experienced this before, even in the Underground.

Deciding not to think on things too hard for the sake of not ruining their time with Asriel, Frisk stands, leaning against the wall when a now-familiar sensation of dizziness overcomes them. 

A few moments later, Asriel walks from the kitchen again, smiling as he walks over to Frisk. “Alright, we can go. And don’t worry, I was just kidding before. I don’t actually plan on pinning you to a tree and having my way with you.”

“You didn’t have to make it sound so tempting, did you Asri?” Frisk teases, leaning against Asriel and hooking their arm around his. “Let’s go already. It’s gonna get dark with all this stuff getting in the way of our romantic walk.”

Asriel smiles, laughing softly. “Yeah, I guess it may do.” The caprine grabs his keys from the bowl left nearby, unlocking and opening the front door. Led by his smaller sibling, Asriel steps outside, locking the door behind them and pocketing the keys.

“Alright, so you said you knew a route we should take?” Frisk enquires, doing what they can to keep pace with Asriel as they begin to walk.

“Kind of? I like to take walks sometimes, and it’s just the way I normally go.” Asriel admits, tightening his grip on Frisk’s arm somewhat. “I don’t think I’ve ever gone on a walk with someone else though. It’s not exactly a date, but it’ll do.”

Frisk blushes lightly, nodding. “It’s weird to think we haven’t actually been on a proper date yet. I mean, I guess we don’t have to. Aren’t dates supposed to be getting to know someone better?”

“I think so? I’ve never actually been on one.” Asriel says, slightly embarrassed. “But if that is true, then yeah. Dating does sound kind of pointless considering we know each other too well.”

Frisk nods in agreement. “And besides, dating would be troo traditional. And, as our relationship is anything but...it’d be weird, right? Not that...actually our whole relationship is weird isnt it?”

Asriel smiles, nudging Frisk gently. “Yeah, it is. I don’t mind, but yeah it’s weird. I can’t think of a lot of other people that are in a romantic relationship with their sibling. Or, I guess for that matter a sexual relationship with them.”

Frisk blushes, noting that Asriel’s naturally loud voice was attracting some rather unwanted stares as they walk through the main street of Ebott, the town founded by monsterkind none too far from where the Barrier once was. “Asri, keep your voice down.”

“Huh? O-oh, right. Oops.” Asriel laughs nervously, consciously trying to speak quieter. “Sorry Frisk, I kinda forgot that my voice is loud.”

“It’s fine, people always looked at me strange anyway. Can’t hurt to give them more reasons, right?” Frisk sighs, their arm dropping from Asriel’s as they jam their hands into the pants pockets, all cheerfulness gone from their voice. “Sorry, Asri. I’m not trying to be miserable.”

“It’s alright Frisk. It must be rough, so you have every right to be miserable about it.” Asriel comforts Frisk, placing a hand on their shoulder. “But c’mon, try to be cheerful if you can alright? I want you to enjoy our walk.”

Frisk nods weakly. “I’ll do my best.” Their voice is quiet, and nervous. Not knowing whether or not they were still being stared at, Frisk simply decided to keep their head down.

“That’s all I can ask for.” Asriel replies with a soft smile, walking alongside Frisk as they turn off from the main street, heading out toward the outskirts, where the forest begins. “You’re a lot braver than you think, Frisk.”

Frisk smiles weakly, looking up through their hair to Asriel. “You really think so? I always thought I was kind of a coward.”

“Well, you aren’t. Who else could have gotten through the entire Underground without harming anyone, trying their hardest to befriend absolutely everyone they came along?” Asriel smiles, pulling Frisk’s hand into his own. “And achieving it too, more importantly.”

Frisk laughs nervously, scratching the back of their neck. “I guess. I don’t really like to think about that, though.” They look away slightly. “It reminds me too much about my past. I don’t want to remember that past.”

Asriel nods, gently stroking Frisk’s palm as they reach the outskirts of town, only the forest in front of them. “Got it. So, you alright walking in the forest with me? No secret fear of trees or anything I don’t know about?”

“The only thing I’m scared of is you getting us lost, Asri.” Frisk replies, nervousness still lingering in their heart, even if not much of it. “Well, that and having difficulty walking back.”

Asriel blushes a little, squeezing Frisk’s hand. “C’mon Frisk, I told you I was joking about that. I don’t actually plan on having sex with you out here.”

Frisk laughs softly. “I know you were joking. But I wasn’t joking when I said it sounded tempting.” The sudden stop of Asriel pulls Frisk’s hand free of his, and Frisk was more than a little surprised to see that Asriel was blushing more furiously than even Frisk ever had; or at least could remember. The bright red was painfully clear even through the fur on Asriel’s cheeks.

“What’s the matter, Asriel? Didn’t expect your younger sibling to be such a pervert? I thought you could read my mind?” Frisk teases, resting a hand on their hip and poking out their tongue. “I bet you’d look at me different if you really delved in there.”

Asriel opens his mouth to reply, but closes it and instead remains silent, unsure of how to reply without sounding too unpleasant. Simply walking past Frisk and into the forest, Asriel finds himself even more embarrassed at the loud laughter that came from Frisk before they caught up soon after.

“Poor little Asri, not sure how to cope with their cute little sibling being a filthy pervert.” Frisk continues, turning and walking backward alongside Asriel, finding a little too much joy in how frustrated and embarrassed he looked. “You really thought that choking and that tongue of yours was as far as it went?”

Asriel flusters, stopping again and glaring at Frisk. “What’s gotten into you Frisk? Why are you being so lewd all of a sudden?”

Frisk stops as well, shrugging. “Maybe I just wanted to embarrass you for a change. It’s hardly fair that you get to make me flustered and annoyed, without any payback. Is it?”

Asriel scowls, looking less embarrassed and much more angry than Frisk had expected. They step back a little, smugness replaced quickly with panic. “I-I was just kidding, Asri. You don’t have to look so-”

The rest of Frisk’s sentence is cut off as Asriel steps up to them suddenly, lifting them by their waist and pushing his weight against them, pinning them to the nearest tree. Hissing quietly at the pain that surged up their back, Frisk found their heart racing and they weren’t sure it was for good reasons.

“Look so what, Frisk?” Asriel growls, smiling against Frisk’s neck as he shifts his weight, breathing directly down Frisk’s spine, causing the smaller human to shiver. “Frustrated that you’d bait me with calling yourself perverse, with no proof at all?”

Frisk swallows hard, resting the back of their head against the bark. “Asriel, what’s gotten into you? I know I was acting weird, but this isn’t like you at all.”

Asriel growls, trailing his tongue over Frisk’s neck and reveling in the subdued, quiet moan that spills from Frisk’s lips. “I don’t care if this is like me, Frisk. You can’t expect to get away with such blatant teasing.”

“Asri, please. I was just kidding around, alright? You can st-oh shit.” Frisk curses quietly, focusing on the rapidly coiling black markings making their way up what parts of Asriel are visible around his clothing.

“I don’t think I asked for you to keep speaking, did I Frisk?” Asriel growls, gently biting into Frisk’s neck, just deep enough to draw blood. Frisk grunts harshly, cursing under their breath which only makes Asriel smile more. “There’s a good little human. Moan for me, let me hear your voice.”

Frisk writhes against Asriel’s inhumanly strong grip, their heart pounding in their chest. Unlike before, Frisk had absolutely no way of fighting against Asriel, or what he wanted to do. Which, right now, seemed to be Frisk themselves.

“Resisting? Come now, Frisk, don’t be so shy. You said you were a pervert, right? So surely you want this. If you truly are perverse, you’d be fine with me taking you right here and now, mere minutes away from town and in plain sight.” Asriel’s voice is harsh, hoarse and far too close to Frisk’ ear for them to be comfortable.

“Asri, stop it. I don’t...I don't want to do this. Please, Asri, let me go.” Frisk pleads, their breathing coming too quickly as their heart races achingly fast in their chest, a heavy numb pain pulling at their heart, but more agonising was the harsh pain pulling at Frisk’s SOUL.

The human didn’t find themselves to be surprised as they heard the quiet, familiar sound of their SOUL being pulled from their body, the small red heart floating in front of their chest. What did shock them, however, was just how severely the changes in Frisk’s SOUL had begun to take hold. The red heart was now covered in veins of white, as if it was cracked.

“Look at that, you see? You really do belong to me, don’t you Frisk? You’ve even started giving up your very SOUL to me.” Asriel laughs, moving a clawed hand to Frisk’s hair and pulling it back, forcing Frisk to look into his eyes. A part of Asriel hated how much he enjoyed Frisk’s panic, and their fear. But a much louder, more dominant part of him wanted more.

“A-Asri, please. Please, don’t touch it. Or me, actually. Please just let me go before you do something you’ll regret.” Frisk begs, their voice quiet and so desperate that it pains the human to hear it. “Please let me go, Asri. I-I promise I won’t tell Mom, please just put me down and let me go home.”

Asriel laughs, a laugh far too familiar to Frisk. Not his usual laugh, but a far darker, more lustful one, nearly exactly how he had laughed at Frisk during the encounter the two had before the Barrier had been broken, while Asriel was in his full Hyperdeath glory.

Frisk’s heart sank, a quiet and subdued whimper the only sound they make as Asriel draws his tongue over Frisk’s neck, a faint trail of gray marking their skin. “Tell her whatever you like, she won’t believe you Frisk. After all, I’m a wonderful son. Why would I ever take advantage of you?”

Frisk knew all they had to do. They just had to last, to cope with the pain and the heartbreak that they knew would follow this. They’d heard those words before, a few days before Frisk had run to Mt Ebott. There’d be no running away this time, Frisk didn’t have that escape. But if they could just cope, just grit their teeth and survive the pain, they’d be fine.

They were always fine. That was what they were good at. Coping with pain, and hatred, and falsehoods. They were good at lying, at saying they were okay.

But they weren’t going to be good at explaining to Toriel what Frisk knew would happen.

After all, Asriel was such a good, well-behaved child. Why would he ever force himself on Frisk?

Frisk would just be lying, she would say. A plea for help because they couldn’t cope with Asriel anymore. They were just a stupid human after all. A stupid, worthless, pointless human who deserved everything they were going to get.

“I’m sorry, Asri. I promise I won’t tease you again, please just let me go.” Frisk’s words were quiet, a desperate plea. It was all they had left in them, anymore.

They knew they wouldn't get an answer.


	10. Mistakes and coming to understand them.

**Notes for the Chapter:**

> Hey everyone, Aithe here. So, this is the first of the re-uploads that I promised everyone. Hopefully this new way of having things happen is better for you all to read. It was certainly easier to write, even if my health has really slowed me down. I'll try to update faster from now on, but please be patient if I'm slow.
> 
> As always, though, any and all feedback is very much appreciated and I hope you enjoy.

The only thing that Frisk could still feel was pain. A hot, coarse pain the shot through their legs as they were dropped to the ground, tears streaming down their cheeks as they sobbed quietly. Fear overtook them as they looked up to Asriel, who was stepping away from them, turning away. 

"Y-you let go." Frisk hated the amount of surprise that was in their voice. "Why did you let me go?" 

Asriel curses under his breath, his whole body crawling with a burning itch that he can never scratch. "I had to. I might be a monster, but I'm not a rapist." His voice was quiet, his hands shaking as he struggled to believe what he had almost done. 

"Why?" Frisk whimpered, barely enough air in their lungs for even the simple word, a quiet and broken plea to their older brother. Lifting their head just enough to see him, Frisk's aching heart only continued to race, seeing that the markings on his fur hadn't faded in the slightest, just as they had expected. 

"I don't know, Frisk. I-I don't know." Asriel choked on his words, tearing at his clothes as he turns back to face Frisk, panic in his eyes. "I can't control this. I can barely even get enough focus to talk." 

Frisk stands, shakily. They feel somewhat lightheaded as they stumble over to Asriel and look up into his eyes. "But you didn’t hurt me. You could have, but you didn't."   
Asriel smiles weakly, nodding as he feels the itching on his skin beginning to pass as the black patterns on his fur begin to fade away. The caprine breathes heavily as the pain subsides, clarity coming back to him. 

"You really had me scared, Asri. I thought...I thought you were going to-" Frisk finds themselves cut off, as Asriel pushes his lips to theirs, the kiss feeling too soft and kind for the racing fear in Frisk's heart. They pull away quickly, embarrassed and surprised at how they're more shocked at being kissed than anything else. 

"I know, Frisk, and I'm sorry. It's so hard to control these urges. I'm trying not to hurt you, I swear." Asriel speaks quietly, as if paranoid someone could be watching them, seeing him being such a hot mess while holding Frisk closely. 

"I know, Asri. I don't understand what it feels like to be possessive, but I believe in you." Frisk replies with a soft smile, kissing Asriel on the cheek. "Just, next time make my heart race for a good reason instead of panic." 

Asriel nods, his own heart slowing to a more reasonable pace. "I think I can do that. I'm sorry for scaring you, Frisk. I won't do this again." 

Frisk nods, their nervousness slowly beginning to subside as they look around, nodding. "Well, we didn't get caught at least. I really wasn't expecting you to react to my flirting in such an over-the-top way, Asri." 

Frisk offers their hand to Asriel, who takes it nervously, the pair beginning to walk deeper into the forest. "It wasn't deliberate. Hyperdeath...it's like a button that I know exists, but don't know how to push it. Or stop myself from pushing it." 

Frisk nods. "I think I get it. I don't really envy you, that sounds pretty torturous. B-but don't worry, I won't tease you again. Since it seems to be a way to push that button." 

Asriel grips Frisk's hand tighter, interlocking his fingers with theirs. "I'm not gonna make these decisions for you. And I don't want to get away with this so easily, either."   
Frisk squeezes Asriel's hand tightly. "You didn't get away with anything. You were just scary because you were Hyperdeath. But now you aren't. You're the normal Asriel that I'm used to. So there's nothing to apologise for." 

Asriel stops, almost pulling Frisk to face him. "No, Frisk. You don't have to be mad at me if you can't bring yourself to be, but you at least need to realise that I almost raped you." 

Frisk nodded weakly, a sad smile on their face. "I know that, Asriel. But the almost is the most important word there. I didn't even have to punch you this time."   
Asriel frowns slightly, somewhat hurt that Frisk was able to take things so lightly. "Frisk-" 

"No, Asriel. We are not dwelling on this." Frisk's voice is stern, and Asriel is briefly reminded of how Toriel would scold him when he was younger. "Nothing happened.   
There was a loss of control that didn't go anywhere and that's as far as this situation is going." 

Asriel nods, ashamed at the embarrassment that flushed through him when Frisk spoke in such authoritative, no-nonsense ways. "G-got it. Sorry." 

Frisk smiled again, stepping forward and wrapping their arms around Asriel's midriff. "Glad to see you can listen when I get serious." 

Asriel winces slightly as the air is driven from his lungs, before the caprine leans down and kisses Frisk atop their head. "I always listen as best I can, Frisk. You're my datefriend after all, in case you forgot." 

"Nope, I didn't forget. I don't just ask anyone to lift me against a tree and fuck me, do I Asriel? That kind of request only goes to you." Frisk smiles at Asriel's embarrassment as they pull free of the embrace, walking ahead of the caprine. 

"That's true. Although I've noticed that you've been flirting with people a lot less, Frisk." Asriel speaks more calmly now, trying to suppress the thoughts running through his head for Frisk's sake. 

"Duh. I have you now. Why would I flirt with anyone who isn't...yknow, my partner? The one I love?" Frisk raises an eyebrow, confused that Asriel could be so clueless. 

"Well, you...Frisk, you're pretty much a legend in Ebott for being so flirtatious. So maybe it's just weird to have all that focused on me." Asriel shrugs, keeping pace with Frisk as they wander around the forest, losing themselves amongst the trees. 

"That's a pretty weird reaction, Asri. Normally if you're in a relationship you want your partner to stop flirting. But hey, if you want me to keep going, I can." Frisk knew they were lying of course. There was no way they'd risk their fledgling, and already struggling relationship over something so stupid as that. 

"I didn't say I wanted you to flirt, Frisk. It's kinda...nice, I guess, being the center of your attention." Asriel admits, embarrassed as he scratches at the back of his neck. "Possessive nature or not, it's nice to feel wanted." 

Frisk smiles slightly, stepping in front of Asriel and hugging him tightly again. "I don't care what your nature is, Asri. You're important to me, and I do want you. I wouldn't be a relationship with you otherwise." 

Asriel smiles weakly, winded from Frisk's sudden embrace which he willingly returns, albeit gently. "I know. Maybe in time my stupid brain will catch up on that too. Well, the part of it that doesn't focus on libido, at least. That part always wants you." 

Frisk blushes slightly, instinctively looking down to see if Asriel had somehow become aroused. Breathing a quiet sigh of relief when they saw that wasn't the case, Frisk tightened the embrace. "You always were a bit of a horndog, weren't you Asri? I mean, it was your fault that we got the lock installed on our bedroom door." 

Asriel groans quietly, hanging his head in embarrassment. "Please don't remind me, Frisk. It was bad enough that you caught me a couple of times back then. But Mom catching me was so, so much worse." 

"Why? Were you worried she was comparing you to Asgore?" Frisk chides, stepping away from Asriel just in case he tried to punch them, as was the common 'Shut up you jerk' response the two used. 

Asriel bleated with embarrassment, hiding his face in his hands. "That's disgusting, Frisk! God, even for you that's so messed up." 

Frisk was barely able to stand as laughter burst from them, having not seen such intense embarrassment on their older sibling in years, since the situations in question in fact. "S-sorry. O-oh fuck, you're so fucking flustered." 

"Of course I am!" Asriel stamped his footpaw, glaring at Frisk while trying not to look too much like he wanted to die from shame. "Y-you just accused Mom of comparing me to her ex-husband, t-that's really fucking gross!" 

Frisk held back most of their laughter, but unable to suppress their giggles at Asriel's embarrassment. "Relax, it was just a joke. Mom might be weird, but she isn't that kind of weird. Maybe." 

Asriel groans, turning away from Frisk and crossing his arms tightly across his chest. "I'm not having this conversation with you. I am not going to theorise the shit that Mom is into." 

Frisk shrugs. "Alright. Although it's kinda stupid to think that situation is weird considering you've literally fucked your younger sibling in the ass." Seeing Asriel's completely crushing embarrassment was bringing Frisk a sick sense of joy, but also a significant amount of worry that it might re-trigger Asriel's anger. 

Asriel turns back to Frisk, a retort fully formed in his head when the wind is driven out of him by Frisk suddenly wrapping him in a tight embrace. Struggling to truly stay angry at Frisk, Asriel sighed deeply, reluctantly wrapping his arms around Frisk. 

"Sorry. I know I shouldn't tease you." Frisk speaks nervously, despite the calm that Asriel's scent always brought them. "And I know I said I wouldn’t, then immediately did. Sorry for being dumb, Asri." 

Asriel smiles softly, tightening his grip on Frisk. "Don't worry so much. I've calmed down now, Frisk. I'm not going to go Hyperdeath on you. Now, do you want to keep walking in the forest or head back to town?" 

Frisk shrugs, nuzzling against Asriel's chest. "I don't care, really. I just want to spend time with you, Asri." 

Asriel blushes slightly, stepping away from Frisk and taking their hands in his. "Then let's keep walking around here. It's quiet, so we don't have to worry about people   
overhearing our weird conversations." 

Frisk nods, smiling warmly. "Sounds good to me, Asri. And don't worry, I won't bring Mom up again." 

"Yeah, you better not." Asriel begins to walk, finding Frisk quickly beginning to keep pace with him. "There's a lot of things I'd really rather not know about Mom and Dad, their sex lives being top of that list." 

Frisk shrugs. "Yeah, I guess. Not that our sex life is all that normal. I mean, how many people can claim that they get to change species because they have sex with their partner?" 

Asriel laughs quietly. "Yeah, that's...I don't think many people at all. I really wouldn't be surprised if you were the first." 

Frisk nods, leaning against Asriel as they continue walking together, hand in hand. "I'm just full of surprises aren't I? Even if I wish that I was able to change outside of sex." 

Asriel tilts his head in confusion. "Really? I thought that I was pretty good in bed. Am I doing something wrong?" 

"Huh? No, not at all. But it'd be faster if we could change me just using encounters instead, wouldn't it?" Frisk questions, beginning to feel slightly worried that they might end up lost in the forest, but hoping Asriel knew well enough to keep that from happening. 

"I guess so. But considering the first time you saw the changes to your SOUL, you passed out...maybe it wouldn't be the best idea, y'know?" Asriel tightens his grip on Frisk's hand somewhat, his heart still pounding in his chest. 

"That’s reasonable. I guess that we'll have to talk with Mom about it at some point." Frisk smiles, blushing slightly as they realise that, despite what had almost transpired, the situation they were in could almost be construed as romantic. 

Asriel nods his agreement, before speaking quietly, despite knowing full well there was nobody around to hear him. "You don't seriously think Mom was comparing me to Asgore, do you?" 

Frisk can't stop themselves from laughing at Asriel's continued embarrassment. "No, I really doubt it. I think our relationship is weird enough without you sleeping with Mom too, Asri." 

The caprine shudders at the thought, an unpleasant shiver crawling down his spine. "Don't ever say things like that again. I think I just threw up in my mouth a little."   
Frisk shrugs, nudging Asriel's arm. "Can't help it that you're so vanilla, Asri. I had such high hopes that you'd be a closet pervert too." 

Asriel growls quietly, shame overcoming him as he slips his hand free of Frisk's own. "Not all of us can be weird, Frisk. And besides, you get a bunch of ideas from that porn stuff you watch, right?" 

Frisk stopped dead in their tracks, a look of desperate confusion on their face. "You're kidding, right? You're honestly trying to say you've never watched porn?" 

Asriel blushes intensely, shaking his head slightly. "No, I haven't. I've heard a lot about it but it sounds kind of gross, watching people who were filmed having sex." 

Frisk tilts their head, still entirely baffled. "Then how the hell did you get through puberty without porn? Especially with a sex-drive like yours?" 

The young caprine turns away, suddenly feeling incredibly hot all over. "I don't really want to share that information with you, Frisk. I'm allowed some secrets aren't I?" 

Frisk steps up behind Asriel, wrapping his arms around his midriff. "I guess if you want to be a spoilsport. Or are you embarrassed all of a sudden?" 

"What do you mean, all of a sudden? You know I don't like talking about sex, Frisk." Asriel whines, wondering who exactly was in charge of this situation. 

"Aww, is that all that it is? I was hoping you were embarrassed because you were thinking of me, or something like that." Frisk finds themselves somewhat shocked at how, despite not trying to tease Asriel, their words just spilled free before they had the chance to think about them. 

They find themselves more shocked, however, when Asriel's pants tighten slightly beneath their grip. "O-oh. I didn't think it was-" 

"Don't, Frisk. Don't talk about it." Asriel pleads, hanging his head from shame. "That was a long time ago, and I thought about a lot of stuff I'm not proud of." 

Frisk shrugs against Asriel's back, letting him go. "I'm not gonna push any further than that, then. I don't want to make you uncomfortable." 

Asriel breathes a heavy sigh of relief, his heart beating fast enough to start hurting. "Thanks, Frisk. I'm sorry that I can't be more open with you." 

"Don't worry so much, Asri. But, do you mind if we head home soon? I don't want to get lost in here." Frisk sounds nervous, their whole body shaking slightly. "I ran through here a long time ago, and I don't wanna remember too much." 

Asriel nods. "Alright, let's head home." 

\---------------------------------------------------- 

Toriel struggles to find something to do with her hands, worry flooding through her. "They've been gone for hours. It's gotten dark, Sans. What if something happened to them?" 

Sans shrugs, leaning back in his chair. "Tori, this is Asriel we're talking about. No offense, but he's too much of a coward to get himself, or Frisk, into a stupid situation. They probably just lost track of time while making out in the forest, or something." 

Toriel sighs, pausing in her pacing and turning to face her husband, visibly shaking from nerves. "Hours, Sans. They left almost four hours ago. No amount of stamina, loving or sexual, excuses that." 

Sans found the timing nearly contrived as both he and Toriel heard the front door being unlocked. "Kid has better timing than me. Should congratulate him on that." 

Toriel glares at her husband, but is instantly overcome with concern as Asriel and Frisk walk into the living room, both of them looking exhausted and Frisk looking as if they were on the verge of a breakdown. 

"What happened, you two? You look like you got yanked through a hedge." Sans questions, unmoving from his position in his chair. 

Asriel holds onto the shaking Frisk carefully, looking between his parents. "I, uh..kind of got us lost. I thought I knew the forest better, but we ended up deeper in than I thought." 

Toriel sighs quietly, placing a hand over her chest as she sighs heavily. "You had me worried sick, both of you. And to think it as all because of your poor sense of direction." 

Asriel smiles weakly, flinching as he hears Frisk sneeze, shivering in his grip. "It's really cold out there, Mom. Can we get Frisk wrapped up or something?" 

Frisk nods weakly, sniffling and rubbing their nose. "Could I have a bath, Mom? I-I'm so cold." 

"Of course, my child. Asriel, take Frisk upstairs and run the bath for them. No funny business, however. If Frisk is coming down with a cold, you shouldn't interfere with them." Toriel is careful not to sound too overbearing, a small smile on her face as she watches her children ascend the stairs. 

After they are upstairs, Toriel walks over to the couch that Sans is sat upon, sinking into it alongside him. "All of this worrying cannot be good for me. Ever since they have become lovers, it feels as if my life is getting shorter." 

Sans leans against Toriel, looking over to the now-empty staircase. "You always did worry a lot, Tori. But, you do know that our kids can look after themselves now, right? They're almost adults." 

The elder caprine sighs, nodding her head. "I know. But they're still our kids, Sans. Just because they're growing up won't change that." 

"I know, Tori. It's weird seeing them get older. The prom was probably weirder for us than it was for them." Sans admits, shifting to get more comfortable. "But we can't control their lives. They're gonna do stupid stuff, because they're kids." 

Toriel sighs, pinching the bridge of her nose. "I know, Sans. But I can't stop myself from getting worried. Our children are in a very complicated relationship." 

"And worrying all the time is gonna make it less complicated? C'mon, Tori, you know better than that. Frisk is far too mature in their own way to do anything stupid. And Asriel is too horns-over-hooves to do anything Frisk doesn't want to." Sans reasons, listening as best he can to hear what his children are up to. 

Toriel groans, suddenly feeling very old. "I understand that, Sans. But I am still their mother, and I will always be concerned. As you should be." 

"I am worried, Tori. But I'm also a lot better at, y'know, not showing it." Sans leans back, resting more comfortably against his wife. "I don't like our kids growing up anymore than you do. But they have their own lives. Together, at that." 

"That is what worries me the most. If anything were to go sour between them, I cannot imagine how much stress the family would be put under. Especially with Asriel's powers." Toriel finds herself tensing and shifting constantly, her whole body proving her anxiety. 

"Then we just have to hope they'll do alright." Sans does what he can to comfort Toriel, knowing this is far from his specialty. "Any more than that may end up causing more harm than good." 

\-------------------------------------------------- 

"How's that, Frisk? Not too hot, is it?" Asriel asks, unsure if his nervousness of seeing Frisk naked was due to what had nearly transpired, or merely because he was concerned as to how it would affect his libido. 

Frisk sighs happily as they sink into the enormous bath, the tension in their muscles uncoiling. "It's perfect. Thank you, Asri. You're a godsend." 

Asriel smiles, fidgeting in place. "Uh, you want me to go now? I can leave you to your bath." 

Frisk shakes their head, resting against the side of the bath as they get as comfortable as they can. "I'd like to talk, Asri. So many things have happened that we haven't had a chance to sit down and just...talk about any of it." 

Asriel nods nervously, removing his shirt. "Do you want me to join you in there? I mean, it'd be kind of weird if I was just sat on the floor or whatever while you're bathing. Unless you don't want me near you. That'd be fair." 

Laughing quietly, Frisk shrugs. "Do whatever you want, Asri. I'm fine with bathing together. We are a couple now, and that's a thing that couples do. I think." 

Asriel nods again, casting his shirt aside before fiddling with the fly on his pants and pulling those off; quickly removing his underwear in short order before climbing into the bath with Frisk, moving over beside them. 

"You don't have to be so nervous, Asriel. It's not like this is the first time we've bathed together, is it?" Frisk questions, leaning against their caprine partner as they relax more completely, sighing happily. 

"Sorry, Frisk. I just...I'm nervous because I got so close to hurting you, and now we're in a bath together." Asriel resists the urge inside him to hold Frisk closer to him, to embrace his younger sibling and feel that connection again. 

"Because I forgive you. You struggled to get control back, but in the end nothing really happened, did it? I mean, I got some bruises on my back, and my legs kinda hurt for a while because you dropped me. But that's all." Frisk looks up toward Asriel, thoroughly unhappy that he seemed so nervous. 

"I can't forgive myself quite so easily, Frisk." Asriel's voice is quiet as he hangs his head, his mind overtaken with thoughts of what could have been, what damage he could have caused Frisk and the family they were a part of. 

The caprine is pulled suddenly from his listlessness as Frisk's weight is pushed onto his thighs, the person in question now sat there and staring up at him. "Asri, come on. I know you get kinda weird after an episode, but it's all going to be okay. And before you worry, I'm not going to stop wanting to have sex with you either." 

"That isn't my concern, although I guess it's nice to know." Asriel can't hide the blush on his cheeks, caused both by embarrassment at the possible intimacy that could easily happen from this position, and the humidity of the bathroom. 

"I mean it, Asriel. This isn't going to change anything. You can't control yourself properly when you go Hyperdeath." Frisk comforts Asriel, gently bringing a hand to the goat-monsters cheek and smiling slightly as he nuzzled into it. 

"I know. I'm going to try and learn how to better resist it." Asriel speaks quietly, his voice somewhat hoarse. "It won't happen again." 

Frisk nods, moving and kissing their lover, revelling in the intimate warmth of his mouth as they do so. "I love you, Asriel. No slip ups, or episodes, are going to change that." 

"I love you too, Frisk. Even if it's a stupid, angry, possessive love sometimes, I love you dearly." Asriel smiles as he leans forward, kissing Frisk gently again. "And I'll never stop loving you. Although, if you don't move, that love might end up becoming a lot more obvious real quick." 

Frisk smiles, giggling quietly before climbing off of Asriel's lap, sitting beside them. "Let's not make a mess in the bath of all places. The cleaning alone would be torture, let alone how angry Mom would get." 

Asriel laughs softly, finding in himself some small amount of strength to wrap his arm around Frisk's midriff, his wet and clingy fur feeling warmer at the touch. "No kidding. But, maybe later tonight, or tomorrow...do you think we could try it again? If you're willing to change some more, that is." 

"That's probably the politest way of asking me for sex that you could possibly come up with. I'm actually kind of impressed." Frisk teases, resting a hand on Asriel's thigh. "But yes, I'd like that, Asri. I think tomorrow is when Mom has that board meeting, so maybe then? We might have the house to ourselves." 

"That sounds good to me."


	11. Experimentation

**Notes for the Chapter:**

> Hey everyone, Aithe here. There's not a lot to say here, other than to tell everyone that I'm most likely going to be updating more slowly for a while. Writer's block keeps popping up and making me much slower, but I'm doing my best.
> 
> As always, please enjoy and I hope to hear from you all.

"But, Mom, me and Asriel had plans today." Frisk pleads, following the tall caprine woman around the house. "I can't just drop this on him like that." 

"Frisk, I understand that you're annoyed. But I need you to come to the meeting with me. You're important to the school and what I'm going to put forward, so your support would be crucial." Toriel replies, pausing and turning to her younger child. 

"But, I...ugh, fine. Fine, fine if you really need me that much, Mom. I guess I'll have to re-arrange with Asriel." Frisk sighs heavily, their shoulders sagging. "Even if I don't see why I'd be needed. Isn't it a school board meeting?" 

"Yes, it is. But that doesn't mean you won't be useful. What with you being a star student and, well, you are famous Frisk. Maybe not so much as you used to be, but you literally changed the world. Your words may help sway people." Toriel admits, blushing slightly. "I need this to work for me, Frisk. And you can help." 

Frisk nods weakly. "A-alright, I get the point Mom. I'll come with you." 

"Thank you Frisk. I promise I'll make it up to you and Asriel for getting in the way of your plans." 

Frisk shrugs. "If it's this important, I'm sure he'll understand. I just hope he won't be too annoyed." 

"I'm sure it will be fine, my child. Now, please go and dress up nicely." Toriel asks, trying not to feel too guilty about breaking up whatever plans her children had made to spend the day together. 

Frisk nods, leaving their mother's company and making their way to their bedroom. Their heart felt heavy with the guilt of having to drop the plans they had made with Asriel. They listlessly rifled through the wardrobe, barely focusing when they took out what they hoped were relatively nice clothes. 

"Frisk? Why exactly are you getting dressed? Isn't that the opposite of what we need to do?" Asriel's voice comes from behind Frisk, shortly followed by a warm, furry embrace around their midriff. 

Frisk sighs quietly, hanging their head. "Sorry, Asri. Mom needs me to go to the board meeting with her. I'm really sorry, I'll make it up to you." 

Asriel sighs quietly. "I guess it was a little too hopeful to think we'd get the free time today, huh? We'll just have to postpone it until another time." 

"Yeah. Sorry, Asri." Frisk sighs quietly, slipping out of their partner's grip and stripping down to adorn their outfit for the day. "I'll make it up to you tonight, alright?" 

"You don't have to, Frisk. If Mom needs you there, she needs you there. Oh, but hey! I have an idea." Asriel says as he walks over to Frisk, moving their arms away from them before placing a hand on their chest. 

"Asri, wha-" Frisk chokes on their words as an intense heat builds in their chest, coiling around their SOUL. Finding themselves suddenly breathless and cripplingly aroused, Frisk glares at Asriel, struggling to find the words to berate him. 

"Sorry. But now you won't have to worry about me missing you, because my fire is currently coiled around your SOUL." Asriel says with a soft smile, leaning down and   
gently kissing Frisk's forehead. "So I'm with you while you're gone." 

Frisk grunts, desperately trying to keep their hands away from their now-aching erection. "Y-you touched my SOUL? Is that why I feel like I should pounce on you right now?" 

Asriel pauses, blushing and scratching at the back of his neck awkwardly. "O-oh, right. I sorta forgot it does that. Sorry Frisk." 

"Sorry nothing! Y-you can't just make me this needy when I'm meant to get dressed to go to a board meeting with Mom!" Frisk squirms, a noticable dark patch growing on their underwear, the only item of clothing currently on them. "A-at least help me out. Please." 

"I'd love to, but you need to get going don't you?" Asriel pulls Frisk up onto their feet, helping them as they stumble slightly. "I'd hate to get Mom angry because I distracted you like this." 

Frisk sighs quietly. "As much as I hate to admit it, you're right. Mom would kill me if we did anything. God, this stupid fire feels almost like heartburn." 

The younger sibling freezes, then sighs deeply. "Goddamnit, now even I'm making stupid puns. Whatever, just...whatever." 

Asriel smiles softly as he watches Frisk dress, admiring how toned Frisk's body is. While they weren't anywhere near as muscular as Asriel himself, Frisk always took very good care of themselves. It showed too, and Asriel often caught himself staring at Frisk at times like this. 

It didn't take long for Frisk to clothe themselves, so once they were done, they brushed themselves down and turned to face Asriel, blushing slightly. "Uh, so...what do you think? Do I look important enough that I won't stand out?" 

Asriel steps up to Frisk, kissing them gently on the forehead. "You look great, Frisk. Now get going, Mom's waiting for you isn't she?" 

Frisk nods, kissing Asriel on the cheek before leaving the room, taking the stairs down two at a time. "Okay, I'm ready Mom." 

Toriel looks Frisk up and down, a small smile on her face as she brings a hand to her younger child's cheek. "You look wonderful, Frisk. Now, we don't want to be late so shall we go?" 

\---------------------- 

Frisk wasn't sure how long had passed since they had sat down at the beginning of the meeting but it felt like months. It wasn't that they didn't understand what was going on, it was simply that Frisk didn't care. They had no real say in anything, and were bored out of their mind. 

To their credit, they did try to look as attentive as possible, but with a constant lingering heat curling and shifting around their SOUL, it was very hard not to lose their cool. The warmth around their SOUL was all too pleasant in all the wrong ways for a situation like this. 

Idly scratching at their chest, Frisk froze as the warmth around their SOUL suddenly got a lot more intense, causing an equally hot blush to rise to their face. Hoping that nobody had noticed, Frisk moved their hand away, gripping tightly at the fabric of their pants. Breathing slowly, Frisk was glad to see that Toriel seemed too caught up in conversation to notice their odd behavior. 

When the hot coils of Asriel's fire tightened, however, Frisk was forced to act. Thankfully, through some amount of luck, it happened when there was a lull in the conversation, so Frisk was able to get Toriel's attention. 

The caprine turned to look at Frisk, concerned when she saw them looking rather uncomfortable. "What is it, my child? Is something wrong?" 

Thinking on the spot, and incredibly grateful for Toriel's assumption, Frisk nodded. "Yeah, I'm kinda overheating in here. Can I go get some air?" 

Toriel nods softly, smiling gently. "Of course, the meeting will be over soon enough anyway. Take all the time you need, I will wait here afterward." 

Uttering a quick thank-you, Frisk struggled not to run out of the boardroom, closing the door carefully behind them before sighing deeply, looking around for the nearest bathroom. Breathing a quiet thanks to whoever signposted this place, Frisk jogged along the corridor, pushing the bathroom door open and closing it behind them. 

Pulling their phone from their pocket, Frisk speed-dialled Asriel, sitting down upon the closed toilet lid. The seconds it took for him to pick up were agonising to Frisk, the arousal now visible in their pants serious enough that they were forced to undo their pants' fly. 

"Hey Frisk, what's up? Are you on the way back?" Asriel sounded all too innocent, and Frisk found it immediately suspicious that he'd act so casually after most likely being the cause of the aches that were currently swarming around their crotch. 

"Don't you dare act so innocent. What the hell did you do to me?" Frisk growls, itching to get themselves off to ease some of the heat running through their body. "Your stupid SOUL-touching crap is playing up." 

Asriel pauses, feeling somewhat surprised that he had been able to affect Frisk over such a distance. "That wasn't intentional. How bad is it?" 

Frisk grunts, shifting their weight as their erection starts leaking into their underwear, causing a dark patch on the gray fabric. "What, you want a picture or something? Turn it off!" 

On the other end of the line, Asriel smiles as he leans back against the wall of his bedroom, rolling a small ball of fire through his fingers and delighting in how angry Frisk sounded while also sounding desperately aroused. "Sure, a picture would be nice." 

The short silence that followed left Asriel curious, and he winced as his text tone rang far too closely to his ear. "There, you ass. I sent it. Now, please stop using your stupid magic." 

"And why would I do that? You must have some privacy right now, if you were able to send me pictures. So let me help you out." Asriel growls quietly, almost able to feel Frisk shivering on the other end of the phone. 

"You can't turn it off, can you?" Frisk groans, now leaning back with their free hand wrapped around their incredibly needy hard-on. 

"No. Not without being there to touch you. So at least let me help." Asriel admits, the small orb of fire disappearing as he uses his free hand to pull his pajama pants out of the way, starting to stroke himself, enjoying the freedom to do so while being the only one at home. 

Frisk grunted quietly, paying as much attention as they could to any potential noises from outside of the bathroom. "Fine. But you owe me big time for this, you jerk." 

"Whatever you say, Frisk. Now, let me hear you moan." Asriel teases, his voice enough to make Frisk shiver even through shitty phone speakers, they soon found out. "Surely you can get away with that." 

Frisk swallows hard, their hand somewhat sticky from their precum. Their grip is barely strong enough to hold onto their phone as they stroke themselves, their chest still burning hot as Asriel's magic continues it's tight grip on their SOUL. "Don't te-tease me, Asriel. You got me into this mess." 

"And I'll be helping you make your own mess soon enough, Frisk." Asriel growls, the caprine hearing a soft, muffled moan through the phone. "That's it, let me hear you. Just because I can't touch you doesn't mean I can't make you cum for me, Frisk." 

Frisk groaned quietly, thrusting against their sticky, desperate grip as they curse quietly. "Why do you have to be so fucking hot, Asri?" Frisk's words are quiet, their voice practically dripping with lust. "God, why couldn't you be here helping?" 

Asriel laughs quietly, his own furred hand stroking his erection as he leans his head back, breathing heavily as he closes his eyes. "Trust me, I wish I was. It was harder than you think to wait this long before screwing with you." 

"This is payback for me leaving, isn't it?" Frisk laughs hoarsely, arching their back as they shift and writhe, panting heavily. "Fuck, is part of your magic making my arousal run faster? I think I'm gonna-" 

"Don't. Not yet." Asriel demands, causing Frisk's words to falter. "I want to see just how much you're willing to obey me." 

Frisk can't stop themselves from whining, their erection twitching in their hand. "Please, don't do this. Please, Asri." 

"Keep stroking yourself, Frisk. Edge yourself for me, won't you?" Asriel smiles, his own quiet moaning now audible to Frisk through the phone speakers. "You don't get to cum until I do." 

"Ugh, you're such a fucking asshole." Frisk replies, their words short and breathless as they reluctantly do as they're told, quiet curses escaping them all the while. "G-goddamnit, my hand is so fucking sticky." 

Asriel laughs quietly, his own breathing harsh and rapid, the caprine panting quietly as he gets closer to his own orgasm. "F-fuck, Frisk. I want to hear you cum. Use my name, Frisk." 

Frisk nods, knowing Asriel can't see it through the phone, before increasing their pace, breathlessly moaning all the while. "S-shit, I can't hold it Asri. I-I'm going to-" 

The rest of their sentence is torn from them, replaced with a deeply lustful moan of their lover's name as they peak, rope after rope of their seed hitting their hand and crotch. 

Before they could question whether or not they'd done well, Asriel's voice came spilling through the speakers of the phone Frisk was barely holding onto. "F-fuck, Frisk, I'm gonna cum. S-shit, I can't-" For the next few moments, all Frisk can hear are Asriel's hoarse moans, interspersed with their own name. 

Once Asriel fell silent, Frisk spoke up quietly. "Thanks, Asri. Not for using my SOUL like a sex-toy, you fucking pervert, but for helping out." 

Asriel laughs quietly. "Glad to be of service, Frisk. Now, I should probably clean up all this matted fur. Why don't you get back to Mom? I'm sure she's curious where you've been." 

"Shit, you're right. Mom said the meeting should be done soon, so we should be back before it gets too late." Frisk speaks quickly and quietly, fixing their clothes as best they could. "I'll see you then, alright?" 

"Alright. Try not to get caught Frisk." Asriel ends the conversation there, hanging up the phone. Looking down over himself, the caprine smiles softly, admiring the thick strands of his gray seed that clung to the fur on his stomach, chest and hand. 

Frisk, on the other hand, tried not to panic too much as they run their hand under the tap, cleaning off the sticky fluid from their fingers. It took far too long, in Frisk's opinion, but they were able to clear it all off. After that, they quickly fixed their pants, and splashed a little water on their face to clear them up a little. 

"That'll have to do." Frisk sighs quietly, fixing their hair and looking into the mirror above the sink. Smiling weakly at their reflection, Frisk admires the way they had started to look since they had begun to change. Their hair, and eyes were the most obvious, but they could swear that something else was beginning to change, even if they couldn't figure out what. 

Sighing quietly and brushing some hair out of their face, Frisk leaves the bathroom and makes their way back to the boardroom, thankful that there was only silence behind the door as they carefully open it, stepping inside to find only Toriel there. 

"Mom? Sorry I took so long. I'm feeling better now." They speak quietly, as nervous as they always were in large, empty rooms like this one. 

Toriel jumps slightly at the sudden sound of Frisk's voice, turning to look at them. "Goodness me, you're quite a mess Frisk. But, as long as you feel better now than before. Shall we get going? As you can see, the meeting is over. I'm sorry you weren't able to particpiate much." 

Frisk shrugs. "It's alright, Mom. As long as I helped, it's all okay." The smile on their face was slightly strained, but genuine enough. "I called Asriel when I was calming down. He's not mad at me having to go to this." 

"Of course, he is your brother. He understands." Toriel smiles, placing a hand on her child's shoulder and leaning down to kiss them atop their head. "Now, let's get you home. After all, the day is still young and I'm more than happy to take Sans somewhere to give you and Asriel the privacy you would have wanted earlier." 

Frisk freezes, a furious red blush rising to their cheeks. "Mom! Jeez, you can't just let me go one day without being gross, can you? You're supposed to be my Mom, and you tease me worse than Asriel." 

Toriel laughs softly, ruffling Frisk's hair. "I'm afraid I cannot help myself, my child. You are simply too adorable when you are flustered." 

"Mom. Let's go home." Frisk pouts, stepping away and crossing their arms over their chest. "Please." 

"Alright, alright. I won't tease you again today, Frisk." Toriel smiles softly, walking with them out of the building. "I cannot promise that will last until tomorrow, however." 

"Ugh, Mom!"


	12. Progress

**Notes for the Chapter:**

> Hey everyone, Aithe here. First off, I want to apologise for how long this took to update. I've been trying my best to write recently, but health problems keep cropping up and slowing me down. Hopefully this will clear sooner rather than later, and I'll be back to normal updating speed, or at least faster than now.
> 
> Secondly, and more importantly, I wanted to thank you guys. I don't think I've ever told you all how grateful I am that you've read this, and how happy I am to recieve all the feedback from you guys. I didn't plan for this to get as well-known as it has, or for it to be this long. Originally, this was just going to be a one-chapter thing but look at what it is now, and that's all thanks to you guys, who've read my work and helped me want to continue. So...yeah. Thank you all, from the bottom of my heart.

"Oh crap. Ohhhh crap." Frisk mutters to themselves, staring at themselves in the mirror. "What the fuck..." 

Holding their hair away from their forehead, Frisk's eyes widen at the small, barely-protruding horns that had appeared there. Frisk couldn't really tell how long they would be, and they certainly were nowhere near as impressive as Asriel's, but they had horns now. 

And they didn't really know what to do with that information. It was all they could do to keep themselves calm as they slowly trailed their fingers along the new growths, as confused as they were excited. 

"Frisk? You in there?" Asriel's voice startles Frisk slightly, causing them to jump before they drop their hair, smiling softly as they see their hair parting around their horns. 

"Yeah. I'm decent, you can come in." Frisk's cheeks redden slightly as they hear their voice crack, happiness clearly getting the better of them. 

Asriel carefully opens the bathroom door, stepping inside before looking to Frisk. Unable to hold back a gasp, the caprine quickly closes the gap between the two, pushing Frisk's hair aside. 

"H-hey, Asri! Don't just do that without warning me." Frisk steps back, almost losing their balance. "I'm excited too, but please don't startle me like that." 

"Sorry. Sorry, sorry. But holy crap, Frisk, this is huge! This shows that we can make these changes without having to have sex, which means we can-" The words spill from Asriel's mouth unabated, only stopped when Frisk clamps a hand over his muzzle. 

"Asri, chill. We can talk it through with Mom when we go downstairs. Alright?" Frisk reasons, smiling softly. "Trust me, I'm every bit as excited as you. This means we can make me into a monster way, way faster than before. And without having to spend weeks in the bedroom making the whole house smell like a brothel." 

Asriel nods, tightly embracing his younger sibling. "This is huge. Really huge." 

"Yes, it is. Now, let's go downstairs." Frisk pushes Asriel away, walking past him and out of the bathroom, walking through to the living room, where they could hear Toriel speaking, likely to Sans, who was out of town for work. 

Hearing Asriel's footsteps behind them, Frisk slowly opens the living room door. "Mom, Dad? Can I, uh...speak to you for a moment?" 

"Of course, my...child." Toriel swallows hard, surprise visible on her expression as Frisk walks into the room proper. "Oh goodness." 

Frisk smiles weakly, walking to the couch and sitting next to their mother. "You've already seen what I want to talk about, huh?" They laugh nervously, hearing Asriel   
walk in as well, the soft sound of him sitting in the armchair coming from behind them. "I woke up with these, Mom. So, it got me and Asriel thinking. Maybe we can get these things to happen outside of the bedroom." 

Toriel can't stop herself from noticing Asriel looking away slightly. Putting two and two together, the elder caprine looks back to Frisk. "You haven't done anything with Asriel recently? Nothing at all?" 

Frisk pauses, stumbling a little on their words so opting simply to shake their head, feeling a pang of guilt about the lie, even though they thought it was for the best. 

Toriel raises an eyebrow, feeling intensely doubtful that she was being given all the information. "Well, if that is true, then honestly I am not sure what could have caused this. Even with the amount of magic present at home, you shouldn't have changed in such a way. Not so quickly as this, at least." 

Frisk shrugs weakly. "Maybe I'm becoming more sensitive to magic, now that I'm starting to become part monster. I mean, I don't understand this much either. But I'm really excited, Mom. This is huge." 

Toriel nods, leaning forward and kissing Frisk on the forehead, between their new horns. "They suit you, Frisk. I'm sure you'll make a very handsome monster when all of this is done." 

Frisk blushes slightly. "Thanks, Mom. How's Dad holding up, is he okay? I heard that there was some problems in the city." 

Toriel sighs quietly, nodding her head. "Nothing near to where your father is, but it doesn't stop me from worrying about him when he goes on business trips like this. If only he had stayed in Ebott and become a teacher, like I wanted." 

Asriel speaks up, leaning comfortably in the armchair. "Mom, you want everyone to be a teacher. Me and Frisk included." 

The elder caprine blushes slightly. "I-I just think that you'd be good for it. Both of you are very clever, after all. And it would be nice to work with more people who I can tolerate." 

"Mom, neither of us are old enough to work yet." Frisk says quietly, hoping not to disappoint her too much. "Can we leave that kind of conversation until we need jobs? I don't want more stress on top of all these changes." 

Toriel smiles weakly. "Of course, how careless of me. I hadn't thought of how confusing all of this must be. Even if it is a small change, it's still significant in it's way. I thought they would be larger than these, though." 

Blushing from the unintended double-meaning behind their mother's words, Frisk laughs nervously. "Well, I'm not all-monster yet. And I'm still a lot smaller than you, or even Asriel. I'll be smaller in a lot of new ways too, most likely. Like horns, for instance." 

"That would make sense." Toriel muses, looking between her children. "But you are being honest about what you and Asriel have been doing, have you not? I do need all of the information I can have, even if it's rather embarrassing for all of us." 

Frisk swallows hard, pausing for a long moment before shaking their head. "I didn't want to admit it, but no. Remember the meeting yesterday, when I had to leave?" 

Raising an eyebrow, Toriel shifts her weight, sitting to face Frisk head-on. "I assume this has something to do with the mess you were in when you came back to me?" 

Frisk nods weakly, laughing nervously. "I felt fine yesterday. Before I left with you, Asriel...touched my SOUL. He did some kind of weird magic that left his fire around my SOUL, and then I got dressed and we went out. Then, later, during the meeting, he did something that made the fire on my SOUL start moving. And, well..." 

"I don't need to hear any more, I can make assumptions as to the rest." Toriel reassures Frisk, before looking to Asriel. "You, on the other hand, Asriel. What do you think you were doing, performing such acts without explaining what they could mean?" 

Asriel shrinks in his chair slightly. "It was spur of the moment, I didn't plan it. And it's not like I even know why it's such a big deal, it wasn't like-" 

"Planned or not, you are not, under any circumstances, to touch Frisk's SOUL again." Toriel's voice is harsh enough to make Frisk flinch, pulling their knees to their chest. "If anything had gone wrong, or you had been more careless than you already were, you could have caused incredible harm." 

"I know it could have been dangerous, but I'm not stupid, Mom." Asriel sits forward, his voice stronger than he expected. "I know how SOUL's work. I know that better than anyone except Alphys. I wouldn't have done it if I didn't think it would be safe." 

"And yet you still did it. Frisk doesn't know as much about SOULS as we do, Asriel. Just because they don't understand the ramifications of what you did, doesn't mean you shouldn't." Toriel balls her fists, well aware that Frisk hated seeing any form of conflict, even one this minor. But she had to put Asriel in his place. 

"I know what I did, Mom. I made the choice deliberately." Asriel's voice is firm, his hands tightly balled into fists as he stares his mother down, trying to keep himself as calm as possible. "I don't know why you keep having problems with my choices with Frisk. Is it really that hard for you to trust me?" 

"When you make decisions like that, yes it is hard to trust you, Asriel." Toriel scolds. "Making such significant decisions without Frisk having knowledge of what you did is incredibly disrespectful." 

"It wasn't like I was going to keep them in the dark forever, Mom! I just...what is wrong with you?!" Asriel's heart drops as he feels himself starting to lose control, ever so slightly. "It's like you don't want me to be happy! Every time I do anything at all, you find a way to criticise it. Whether it's a small thing, or a bigger decision. You always, always shoot me down and make me feel like shit." 

Toriel finds herself unable to respond, shaken that Asriel thought of her that way, and more so that she agreed with him. She had always thought herself fair, but perhaps she had been too harsh on Asriel. 

"I know that Frisk is always going to be your favorite, Mom. I just wish you were fairer to me, sometimes." Asriel sighs quietly, wiping at his eyes to stop himself from tearing up. "I mean, it's not much to ask to have my decisions respected, is it? To have you actually trust in me for once?" 

"Stop it. Please, both of you, stop." Frisk finally speaks up, their voice quiet and showing just how fearful they felt. "Why do you have to fight? I just wanted to show Mom my new horns and now everything went to shit and it's all my fault, isn't it?" 

"No, Frisk, this isn't your fault. Your brother is right, I have been too hard on him. If anyone is to be blamed for this, it's me. I'm sorry for causing this." Toriel speaks quietly, her heart feeling particularly heavy in her chest. "I am simply trying to look out for you both." 

Asriel sighs quietly, wringing his hands. "I wasn't exactly fair either, Mom. Just because I know about SOULs, doesn't mean I should have done what I did. Especially not without Frisk understanding properly." 

Frisk looks over to Asriel, curious. "What exactly is the big deal, anyway? I mean, I know SOULs are important, but I don't understand why you two need to fight over it." 

Asriel laughs nervously, looking to Toriel for aid before relenting and speaking up. "Frisk, touching someone's SOUL like that is...it's a pretty huge deal. Like, the kind of thing a monster only really does with the person they're married to. Since a SOUL is literally the embodiment of someone's existence, there's nothing more intimate than it. As you found out." 

Much to Asriel's relief, Toriel picks up from there, gently placing a hand on Frisk's shoulder. "Your brother is right. Even myself and Sans rarely do things like that, so for Asriel to do it is rather significant. It's nearly as significant as a marriage proposal, to put it to more human terms." 

Frisk paled slightly, their eyes widening as they turn back to Asriel who, to his credit, looked very embarrassed and somewhat ashamed of himself. "You didn't think to tell me? I mean, if it's that big of a deal, Asri, you could have at least asked first." 

"I know, Frisk. I shouldn't have done it so casually. I guess I'm more willing to commit permanently than you are." Asriel shrugs, his heart sinking to his stomach. "Or at least, I'm more of an idiot who thinks it's okay to move that fast." 

Frisk feels compelled to answer, but finds no words coming to them. They hadn't known how important Asriel's actions were, nor that he was so clearly wanting a permanent relationship, something that Frisk themselves hadn't really considered. 

"Asriel, do you honestly know why you did what you did?" Toriel asks, now calmer but intensely curious as to the reasoning behind her son's actions. "After all, you have not been with Frisk long." 

Asriel shrugs weakly, feeling disheartened. "I just...I guess I want more out of Frisk than Frisk wants out of me. I mean, it wasn't like I started all of this on a whim, I've loved Frisk like this for years." 

Frisk blushes heavily at hearing Asriel's admission, surprised to hear him continue beyond that. "I've always wanted to be with Frisk, I guess. Ever since I understood what romantic love was, I knew I had that for them. It just...didn't seem like as much of a big deal for me to touch their SOUL because I'm more in love with them than they are with me." 

Frisk locks up, wringing their hands in the hem of their shirt. That wasn't true, as far as Frisk was aware. They knew they were hopelessly in love with Asriel, after all.   
They were just a lot more shy, and panicked a lot easier when it came to actual romance. Flirting was one thing, but actually being in a happy relationship constantly confused them. 

"That's not true, Asri. I-I love you just as much as you love me." Their voice is quiet, audibly nervous as they find themselves unable to do so much as look at Asriel.   
"I just don't know how to...do relationships. And it's more difficult because you're my brother. I don't know how to give you all the stuff that you want." 

"I think I should leave you two to organise this amongst yourselves." Toriel speaks before Asriel can reply, standing from the couch and brushing herself down. "I'll find some way to entertain myself in town for a while." 

Neither Asriel nor Frisk could find any way to answer their mother's sudden change in opinion, simply watching as she left the room. 

Once she was out of earshot, Asriel finally spoke up. "I think she's assuming we'll figure this out in the bedroom or something." 

"Most likely. But, Asri, I'm being serious. I might not have fallen in love with you as early as you had for me, but I love the hell out of you." Frisk finds themselves somewhat surprised about how strong they felt in this. "I don't understand why you'd think I don't love you as much as you love me." 

"I guess I just...I don't really know my reasons, if I'm honest Frisk. It was really just kind of a stupid assumption. Since we've never really had a proper conversation about our relationship, I just assumed that I was right." Asriel admits, shrugging weakly. "Love is weird, and it's difficult. And like you said, it's harder because we're siblings. There's nothing really...new with us., y'know? We act the same as we used to, just with more physical stuff." 

Frisk nods. "Yeah, that's true. I mean, we were kind of able to skip the whole dating thing since we already know everything about each other. But I need you to   
understand that I love you every bit as much as you love me. L-like, if you had asked me about doing the SOUL thing you did, I would have said yes. I'm not saying I want to get married or anything, but I would have been more than happy to let you touch my SOUL, Asriel." 

Asriel smiles warmly, standing from his chair and walking over to the couch that Frisk was sat upon, sitting down next to them and taking the human's hands in his own. "I didn't really get it, then did I? I was so convinced that I loved you more, that I never considered that our relationship was actually healthy." 

"You never were very good at understanding other people's emotions, Asriel." Frisk replies with a soft smile, feeling an intense sense of calm overtaking them from Asriel's warm hands. "But we can work on that." 

Asriel nods, smiling as he leans forward and kisses Frisk's forehead. "We can, for sure. But, seeing as Mom is out of the house now, and wasn't yesterday..." 

"Asri, no. You goddamn horndog, we are not having sex just because Mom is out right now." Frisk groans, looking thoroughly unimpressed. "I mean, I'm as eager as you to get me all monster-y, but still." 

"Aww, come on! With Dad out of town for the next week or so, we only need to worry about Mom. And she isn't here." Asriel pleads, his hands gripping Frisk's tightly. "So we have time now." 

"Asri, I said no. I'm not like you, I don't constantly want to have sex with everything nearby that's attractive." Frisk replies, pulling their hands free of Asriel's grip. "I have self-control that you seem to be lacking." 

Asriel pouts, playfully glaring at his younger sibling. "You have to be a spoilsport, with all of your stupid control over your libido and stuff. Why couldn't you just be like me, and want to have sex constantly?" 

"Because that wouldn't be as fun, would it?" Frisk teases, turning and shifting back so their back is against the arm of the couch. "But seriously, it's better this way.   
I'm sure we'll get the time soon but I'm just not feeling it right now." 

Asriel shrugs, smiling softly. "Fine by me, I know better than to push. I mean, it's a shame but I suppose that if you can somehow resist the wonder that is my body, I guess there's nothing I can do about that." 

Frisk laughs softly. "Please, I think you overestimate yourself a little Asri. I mean, I resisted a lot of very attractive monsters in the Underground." 

"Resisted? Is that what you call flirting with literally everyone you could, including Mom?" Asriel replies with a smirk, laughing at Frisk's sudden embarrassment. 

"Okay, maybe resisted is the wrong word. But I didn't sleep with any of them." Frisk retorts, fully aware that they had no real chance of winning this argument anymore. Not that that would stop them trying, of course. 

"You were ten. I'd be scared if you had slept with any of them, Frisk." Asriel replies, smiling smugly at Frisk's failure to hide their frustration. "Don't look at me like that. It's not like it wouldn't have been messed up. Hell, it would still be weird if you wanted to sleep with any of the guys you met down there, right?" 

Frisk shrugs. "I mean, yeah. Undyne and Alphys are married now, so there's that. Uncle Papyrus is...Uncle Papyrus. Mettaton is a robot and I don't even want to think about how that would work. Then there's Uncle Asgore and, if I'm gonna be honest, he is really damned attractive. But he also looks like he'd rip me open." 

Asriel shivers at how brutally honest Frisk is, having not even come close to expecting an answer like the one he had gotten. "That was...a little too much detail, don't you think Frisk? A yes or no would have suff-wait. You don't actually want to sleep with-" 

"No, I don't. Like I said, Asgore is hot. But he's also my uncle, and like...twice my height almost. I'm too small for you, let alone him." Frisk replies a little too calmly for Asriel's taste, especially given the conversation topic. 

"First off, I'm your brother so don't use the whole being family thing as an excuse." Asriel retorts, leaning toward Frisk as he does so. "Second, are you trying to say that if you were about Mom's height or so, you'd try it with him?" 

Frisk shrugs, delighting in how Asriel was squirming at their honesty. "Maybe, I don't know. It's not like that'll ever happen anyway. I'm more than happy with you, even if you're an overprotective idiot." 

Asriel blushes slightly, pushing his weight off the couch and crawling over Frisk, straddling their waist and looking down to his younger sibling, who was now looking up to him. "I'm overprotective because I'm still your older brother. Regardless of if we're more than that, I'm still always gonna be the older sibling. And you better not forget it." 

"How could I forget it with you constantly reminding me?" Frisk teases, poking their tongue out. "It's always with the age thing with you. You're a month older, Asriel, it's not like it's much." 

"I'm still older. And always will be." Asriel pouts, only making Frisk enjoy his annoyance more. "You're just jealous, that's all." 

"Yeah, you keep telling yourself that, goatboy. I'm sure there's so much to be jealous of about someone an entire month older than me." Frisk smirks, leaning back and finding a bizarre form of comfort in Asriel's weight on their thighs. A small part of Frisk finally felt as if they belonged. Like this was their real family, and Asriel their real partner. 

The human locked up a little at those thoughts, harking back to a past they had desperately tried to suppress and remove from their memories. 

Seeing Frisk freeze as they had concerned Asriel, and he gently placed a hand on their shoulder. "Frisk, you okay? You don't look so hot all of a sudden. What happened?" 

Frisk looks up to Asriel, feeling disturbingly empty all of a sudden. "I don't know. Just...weird thoughts. I should be alright, don't worry so much." 

Asriel only finds his concern worsening, having never seen such an empty, vacant look to his younger sibling. Asriel knew very little about Frisk's life before they had fallen to the Underground, but it didn't take a genius to figure out that it had something to do with that. "I will worry, Frisk. What kind of thoughts were they? Were they about your past?" 

Intensely hesitant to answer, Frisk pauses for a long moment before nodding. "Yeah, kind of. I just...it's weird, y'know? I feel so happy and then all of a sudden my head decides to remind me of how miserable I used to be, and it takes my good mood away." They shrug weakly, their eyes still locked with Asriel's. 

"That sounds awful." Asriel replies, sighing softly. "I won't lie to you and say I understand how that feels, because I don't. But if you need someone to talk to about those kind of things, that's what I'm here for." 

Frisk nods, life finally returning to their eyes as they smile weakly, their heart not feeling quite so weak anymore. "Yeah, I know. It shouldn't be a problem, but if it starts being one, I'll let you know. Sound good?" 

Asriel nods, leaning down and embracing Frisk tightly. "Thanks for trusting me, Frisk." 

"Of course I trust you, you idiot. You're my older brother, as you so constantly remind me." 

The caprine smiles, shrugging and letting Frisk go, shifting to allow Frisk greater comfort as he remains atop them. "At last you catch on. I'm here to protect you, alright? Whether you need protecting from humans, monsters or your own head, I'm here. As your older brother, and your partner." 

Frisk nods, smiling happily. "Yeah, I know. Thanks, Asri, really. I don't ever really thank you for all the stuff you do for me, so...thanks. I don't know what I'd do without you." 

Asriel returns the smile, shrugging weakly. "Honestly, I don't know either. But hopefully we'll never have to find out. Y'know, seeing as I plan on being with you until we grow old. And, seeing as I'm a Boss Monster and you're becoming one...that's a really long time." 

Frisk can't stop themselves from blushing at Asriel's admission, even if they had already known such things. They had never doubted that Asriel loved them enough to want to spend their lives together, but hearing it aloud was something else entirely. 

"That sounds like a good plan to me. Even if we don't know how long it will take to get through all of the changes, I like the idea of growing old with you, Asri. Just as long as you don't start looking for a wedding ring any time soon." 

"You're kidding, right? I'm way too poor for that kind of thing. Although I guess that means I should start saving, doesn’t it?"


	13. Changing roles, at least for now.

**Notes for the Chapter:**

> Hey everyone, Aithe here. I'm finally feeling well enough to write at a decent pace again, and am feeling more than a little happy to finally get this chapter done and posted. I don't really have all that much to say about it, so...yeah, just enjoy. As always, feedback is appreciated and I'm grateful for your patience.

"I really wish that you wouldn't keep teasing me Asri." 

"I can't help it, you're adorable when you can't control yourself properly." Asriel replies with a smile, watching his younger sibling's reactions with perhaps a little too much glee. 

"You did this to me, you jerk, now take responsibility!" Frisk yelps as they stumble a little, finding balance to be particularly difficult. "It's your fault my body is doing this, now help me out!" 

"Nope. You can't blame me for your body going these particular changes, Frisk. And you gotta get used to them, since we can't un-change you." Asriel smiles, relenting and holding his hand out for Frisk to grab. 

"I wasn't expecting fur to happen this early. And I really wasn't expecting paws." Frisk takes Asriel's hand in their own, walking toward him and stumbling into him as they fall, unbalanced on their new footpaws. "I look like a fawn or something, this is ridiculous. I look so stupid." 

"You look wonderful Frisk. I mean, yeah it's a little goofy that only your legs have changed, and you grew paws. And yeah, it really sucked to see you in that much pain. But you got through it, and this is the biggest change yet." Asriel holds Frisk close to him, gently running his fingers through the smaller sibling's two-tone hair, which was now mostly white. 

"I guess. It was kinda naïve of me to think it was going to be easy and painless huh? I didn't really think about the fact my skeleton is getting messed around with, let alone all the other shit." Frisk grunts quietly, a few sparks of pain coiling up their legs. "If this is how badly it hurts to just have my legs change, I don't even want to think about how painful other parts will be." 

"You'll get through it Frisk. Even if it takes weeks, and all the medicine and healing magic we can put into you." Asriel coils a few strands of Frisk's hair around his fingers, feeling the younger sibling's heartbeat against him. "Give it time, and we'll make a monster out of you. It would probably be faster and easier if these changes could be kickstarted by something other than sexual things, but that's something we just kinda have to deal with." 

"There are a lot of worse ways to make it happen, for sure. I just wish it didn't hurt so much, Asri. I'd say I never want to feel that much pain again, but I'm going to have to, and I don't know how many more times." Frisk sighs heavily, carefully pulling away from Asriel's grip and stepping back, trying to find balance on their new appendages. "I can only hope that the next few times will be as short as this one. A few hours, I can probably cope with again. But any longer than that and I start to worry." 

Asriel nods, sliding his hands into his pockets. "You're gonna be fine though, Frisk. Now we know your body is more accepting of magic than it used to be, we can use more healing magic next time if we need to. Speaking of which, how are you holding up? Do you need some more help?" 

Frisk shakes their head, wobbling a little as they do so. "Nope, I'll be alright. There's still pain, but it's manageable. I can't rely too much on magic, if I'm gonna make it through the next few times." 

Asriel frowns a little, clearly unsure of Frisk's logic. "That...sure, I'll trust you. But don't refuse just to be stubborn alright? I need you to be safe, Frisk." 

"I know, Asri. I'll be fine, as long as I'm careful. And as long as I'm not stood up much longer, I'm feeling shaky." Frisk's voice cracks a little, moments before they cough harshly, a hand pressed against their chest. "Ow. God, why does my chest feel like it's caving in?" 

Suddenly feeling intensely panicked, Asriel closes the gap between them, gently putting his hands on Frisk's shoulders. "What kind of pain is it, Frisk? Is it similar to how your legs hurt yesterday?" 

Frisk shrugs weakly, feeling lightheaded and dizzy as they stumble forward, leaning against Asriel. "Kind of? I don't know. It just hurts. It's really tight, and it's hard to breathe." 

Overtaken with concern, Asriel scoops Frisk up into his arms, a little surprised at how Frisk's new anatomy had increased their weight as much as it had, before walking them over to the bed and carefully lying his younger sibling upon it. "You need rest. Something is wrong, or maybe this is a change of some kind. I'll go get Mom." 

Frisk nods weakly, screwing their eyes closed as they curl up on themselves, coughing weakly. "Alright. Go on. I'll be okay." 

Struggling to keep his fear in check, Asriel nods, turning and half-running from the room, taking the stairs down three at a time and very nearly losing his balance at the bottom of the stairs. Regaining himself, the caprine breathes deeply, brushing himself down and counting to ten, regulating his breathing before walking through to the kitchen, hoping that Toriel hadn't gone out at some point without telling him. She had a habit of forgetting to tell her children that she had things planned, after all. 

Groaning audibly at the empty kitchen, and the piece of paper in the place Toriel would always leave notes for him or Frisk, Asriel walks over to the note, quickly scanning it for a time that Toriel would be coming back. "Looks like I'm in charge for now. Shit." 

Getting back to his bedroom as soon as he could, Asriel froze when he saw Frisk curled up against themselves, quietly sobbing as they shook and squirmed, whatever pain had overtaken them suddenly clearly being far more serious than either of them had been expecting. 

Cursing quietly, the caprine quickly closes the gap between him and Frisk, kneeling down carefully. "Frisk. Hey, I'm back. Mom wandered off again, so I'm gonna do everything I can to help you, alright. Can you lie on your back now?" 

Frisk looks up to Asriel, their eyes reddened and a little swollen from tears, before nodding weakly and rolling onto their back, whimpering quietly as a sharp spike of pain tears its way down their spine. Unable to even cry out in pain, they simply swallow hard, wincing as Asriel's weight shifts the mattress underneath them. 

"Sorry. Sorry, I know it hurts. I'm not as good at this healing magic thing than Mom, but I'm gonna do what I can. This is a magical pain, so a magical cure is all I can try." Asriel smiles softly, gently placing his hands over Frisk's chest, closing his eyes and focusing intently. 

Frisk gasps as Asriel's hands heat up against them, a deep, blissfully pleasant warmth flowing through the muscles in their chest. Panting quietly as the magical heat coils it's way around their insides, Frisk finds themselves unable to stop their back from arching, bucking up against Asriel, who was currently straddling them to keep them in place. 

Feeling Frisk writhe underneath him, Asriel opens his eyes, reducing the magical flow through Frisk. "Looks like it's working. How do you feel, can you talk?" 

Frisk swallows hard, before nodding. "Y-yeah. Warm. I feel warm. Like when I went to the meeting, but muscles. Not SOUL." 

Asriel nods. "Good, that means it took. It might take a couple of minutes, but I managed to put a good amount of healing magic into you. It'll clean up whatever that pain is, and might even get rid of the bruises on your back." 

Frisk shifts a little more, the heat inside them coiling deep into their body and worming its way down, running through every muscle in their body. "R-really warm. Too warm. Why am I so warm, Asri?" 

"It'll do that. You'll be okay, though. I promise." Asriel reassures his younger sibling, leaning down and gently pushing their hair away from their face, kissing them gently on the forehead. 

Frisk squirms, panting quietly as they feel themselves rapidly overheating, noticing also that this particular warmth wasn't too unlike when Asriel had touched their SOUL. "This won't make me aroused, will it? Your magic always makes me aroused, doesn’t it?" 

"This shouldn't. It's healing, after all. And it didn't make you hard when Mom did it, and she was in the same spot I am. If anything will make you aroused here, it'll be me. And I don't think I should." Asriel replies softly, hoping that he sounded more convincing than he thought he did. In truth, he had no idea what effects his healing magic would have. 

Frisk hoped that Asriel was right. They didn't know whether they wanted to be aroused by this or not, if only to give themselves some sort of distraction from the heat and the lingering pains. But they certainly did know that they were not, under any circumstances, going to correct Asriel that when Toriel had used healing magic, they had in fact become cripplingly aroused, and had spent the entire time Asriel was gone apologising profusely. 

"Since I have no idea how long this might take to properly kick in, or when Mom will be back, should I run us a bath or something? That way I can keep an eye on you, and we can keep the temperature controlled." Asriel asks softly, climbing off of Frisk's waist and helping them into a seated position. 

"Yeah, that sounds good. It'll help me learn how heavy wet fur is, too." Frisk admits, leaning heavily against Asriel as he helps them up, the pair walking from the bedroom to the bathroom next door. "Not feeling quite as warm, now, either. Still warm, but not like my muscles are dipped in lava." 

"That must be the magic settling into you. I guess. I don't really know a whole lot about it, if I'm honest. I just know how to use that magic because Mom taught it to me in case something like this happened." Asriel admits shyly, making sure Frisk can stand by themselves before walking over to the bath and running the water, the sound of it helping relax him slightly. 

"I'm glad she did." Frisk admits, finding strength to talk properly again now that the heat around their lungs had reduced somewhat. "Hey, uhm, Asri? You...don't mind that my fur isn't white like everyone else's, right?" 

Asriel looks over to Frisk, tilting his head a little in confusion. "Why would I mind? I mean, it's not like it's really a surprise. Your skin isn't white, so why would your fur be white?" 

Frisk shrugs weakly. "I just kinda thought it would be. You, Mom and Asgore all have white fur. But mine's brown. And not even a nice brown, just...kinda crappy looking." 

Asriel glares at Frisk, placing his hand on their shoulder. "Don't say that. It looks great. You look great, Frisk. White fur or brown, I love you all the same. And besides, it looks perfect for you. I couldn't imagine you with white fur, either. It wouldn't be the same." 

Frisk startles slightly at Asriel's tight grip on their shoulder, blushing slightly. "Thanks, Asri. I guess I'll have to learn to like how I'll look once all this is over." 

"And I'll be helping with that. Mostly by constantly reminding you how incredibly attractive you are." Asriel teases, leaning down and kissing Frisk softly for a brief moment. "I love you Frisk." 

"I love you too, Asri." Frisk replies quietly, feeling an all too familiar tightness in their pants as they blush heavily. "Uh, the water. Don't let it get too hot." 

"Oh, right!" Asriel laughs nervously, turning back to the bath and running the cold water to mitigate the heat from the hot tap, checking the temperature as Frisk sighs silently, wishing desperately for their arousal to subside. "Say...Frisk?" 

"Yeah?" 

"Since Mom isn't here. I'd...I was wondering if you wanted me to help push you through some...ugh, screw it. I'm horny, Frisk. I want you. If you're alright with that, so soon after the pain." Asriel's voice is laced with nervousness, as he focuses on the swirling waves in the water. "We don't have to. I can go and...get off, before joining you in here." 

Frisk smiles softly, feeling a little surprised that Asriel was still nervous about these kind of things, considering they'd had sex at least half a dozen times by now. Not that they could blame him, they still felt nervous each time. "I don't think my body can handle having you inside it right now, Asri. I'm okay enough to have sex, but I don't think I can take you in me right now." 

Asriel pauses, before turning the water off and turning around to face Frisk. "You're sure you're okay enough to do that? You were curled up and crying in pain like...two, three minutes ago tops. I'm not sure even my magic is potent enough for that." 

"I'm sure, Asri. I mean, I'm horny too. Seems your magic has a perfect record for getting me hard." Frisk teases, pulling their shirt over their head and pulling their pants down, the underwear that Asriel had let them borrow clearly tented as they smile to Asriel, who was now looking rather embarrassed. "See?" 

Asriel nods, swallowing as he steps up to Frisk, embracing them tightly. "Then what do you suggest we do? If you can't take me, how will we do this?" 

Frisk ponders for a brief moment, before quietly uttering the only answer they could immediately think of. "W-why don't we change it up? I mean, I've always been the taker. Why don't you take me inside you this time?" 

Asriel freezes, entirely taken aback by the answer Frisk gave. It wasn't as if he hadn't thought of it as a possibility, he just never thought too much about it. So, to have Frisk bring it up was somewhat of a surprise. "Is that what you want? I mean, I've never done it but I guess I could try to if that's what you want." 

"I don't want you to if you aren't comfortable with it, Asri. We can work something else out if you don't feel up to it." Frisk smiles nervously, shifting as they feel the fabric of the underwear pulling tightly against them, noticing only now that they felt...heavier, down there. 

Pushing those thoughts aside for now, Frisk gently places their hand on Asriel's cheek. "I'm not gonna make you do anything you aren't okay with, Asri." 

Asriel smiles, nuzzling into Frisk's hand as he does so. "I said I could try it if you want. It's not that I'm uncomfortable with it, I just didn't expect you to ask it of me."   
The elder sibling then gently places his hands on Frisk's hips, pulling them flush up against him. "I'm happy to try it for you, Frisk. I promise." 

Frisk smiles, blushing slightly as they feel their erection pushed up against Asriel. "Alright, then. But we shouldn't do it in the bath. I don't want to clean up any mess afterward." 

Asriel nods, stepping away from Frisk. "Yeah, it'd suck to clean off any mess from the bath. Hmm, but the water is warm right now, and won't be if we go back to the bedroom. Ugh...screw it, I'll clean if we need to." 

Frisk blushes more heavily at hearing Asriel's words, their needy erection twitching against it's cloth prison. "O-okay, sure? I mean, I was just trying to save us some work, but if you want to, I won't say no." 

"Good to hear." Asriel teases, pulling his shirt up and over his head, the fabric nearly getting caught on his long, curved horns. "If it starts being too much for you to take though, we'll stop. I don't want to trigger a new set of pains because of this." 

Frisk nods, doing everything they can not to stare at Asriel's muscular form. Keeping eye-contact never felt harder than it did in these situations, Frisk found. "Got it. I'll let you know if it gets too bad, Asri." 

The caprine smiles, a little embarrassed at how much Frisk seemed to enjoy staring at him when he was naked, or at least partially so. He knew he was decently built, but Frisk always made it seem like he was much more attractive than he ever felt he was. 

Trying not to focus too much on those particular thoughts for fear that it might end up dampening his mood, Asriel hooked two clawed fingers beneath the waistband of his sweatpants, puling the fabric away from him and letting it drop, kicking them away when they hit the floor. 

Now in as little clothing has his younger sibling, Asriel looked at Frisk, a small blush on his cheeks. "Do I look alright?" 

Frisk only smiles, stepping up to Asriel and grabbing his shoulder, pulling the taller sibling down into a kiss. Feeling Asriel's inhuman facial structure against them had felt unusual the first few times that they had kissed, but now Frisk couldn't imagine ever feeling anything different as they bit into Asriel's lip, sliding their tongue against his as the caprine's mouth opened. 

The pair stayed locked like that for a few, long seconds before Asriel pulls away, his heart pounding in his chest. He had expected a spoken answer, and as such had found it hard to breathe for a few moments after releasing himself from Frisk's needy kiss. 

"Does that answer your question, Asri?" Frisk teases, winking at him before moving their hand down from his shoulder, over his collarbone and down to his chest, their slender fingers slowly tracing over the muscles clearly visible beneath Asriel's thin fur. "If not, I could always show you how beautiful I think you are." 

Asriel only blushes harder, feeling his own underwear beginning to strain against him at Frisk's gentle touch. This wasn't the first time Frisk had acted like this, but it always took Asriel by surprise to see his normally timid and soft-spoken sibling so openly praise him. It also worried him slightly that, if he reacted too openly to it, that Frisk might catch on to the fact he had a rather well-hidden praise kink. 

"I'm not hearing an answer, big brother. Perhaps you need me to keep going." Frisk speaks softly, leaning against Asriel's tense body, taking care to be as delicate as possible when they trailed their fingers over Asriel's stomach muscles, stopping only when they reached the waistband of his underwear. "After all, you always compliment me but I so rarely reciprocate. Surely I should change that." 

Asriel forced himself to act at this point, grabbing Frisk's wrist and stepping away from them, blushing furiously as he struggles to find strength in his chest to speak. "Frisk, chill. I'm sorry for making you like this, alright, I should have been more careful with my magic. But can you please stop acting like this?" 

Frisk tilts their head a little, their hair falling aside as they look at Asriel, confused. "Acting like what? I was being serious, Asriel. I don't compliment you anywhere near as much as I should." Their hands fall to their sides as they smile weakly. "Did I go too far?" 

"It's not that. I just...I don't know, Frisk. I'm just worried that you're acting weird because of the changes. You've not been yourself." Asriel sighs, feeling his arousal beginning to fade as he sits on the side of the bath. "You're a lot more forward, and I don't want to make it seem like I'm taking advantage of that." 

Frisk smiles softly, walking up to Asriel and sitting beside him, placing their hand over his larger, furred one. "You aren't taking advantage of anything, Asri. I mean, yeah, I'll admit that I'm acting differently, but that's just because I'm starting to feel more comfortable in my own body, now that it's becoming what I want it to be. It's a lot easier to be brave when you like your body, yknow?" 

Asriel smiles, feeling a little foolish as he lowers his head. "Right, of course. I guess it makes sense that self-esteem is tied to your body, huh? That's something that happens with humans. But seriously, you don't have to worry about complimenting me. It's not like you need to, or anything. I compliment you so often because that's what I do. It's what I'm comfortable with, so you don't have to care about reciprocating." 

Frisk shakes their head, interlocking their fingers with Asriel's. "No, I will care about reciprocating. It's not fair that it's so one-sided, especially when you have so many things about you that are worth complimenting, Asri." 

The elder sibling blushes slightly, his embarrassment only deepening. "Well, whatever you feel most comfortable with, Frisk. Now, shouldn't we get in the bath before it gets too cold? Mom will be mad at us if we waste all this water." 

Frisk nods, standing and pulling their underwear down, leaning down to kiss Asriel on the forehead as they do so, before climbing into the bath and sinking into the, thankfully still-hot water, immediately feeling some of the tension in their muscles melting away. 

Asriel struggles to hold back any groans of annoyance at Frisk's deliberately teasing actions, removing his own underwear and joining Frisk in the bath mere moments later. "Why do you like kissing me so much, anyway?" 

"Hm?" Frisk looks to Asriel, before shrugging weakly. "I don't know, it's fun? Do I really need a reason to want to kiss my boyfriend?" 

Asriel pauses, blushing slightly and sinking deeper under the water. "I guess if you put it that way, maybe not." 

"Aww, are you embarrassed at being reminded of that title, Asri?" Frisk teases, pushing themselves over Asriel's waist and straddling him. "Surely you didn't forget that's what you are, did you?" 

Asriel only blushes more fiercely, now much more aware that, while his own arousal had faded somewhat, Frisk's hadn't; as was made obvious by the erection currently pressed against his stomach, which he could have sworn felt larger than before. "No, I didn’t forget. How could I possibly forget, Frisk?" 

Frisk smiles slightly, leaning more heavily against Asriel. "That blush must mean you've noticed, hm? Goodness, Asriel, don’t try and tell me you didn't realise that magically-induced arousal won't go away until it's used up." 

Asriel smiles weakly. "Actually, I didn't realise. This is news to me, Frisk." 

"Hmm, well that's alright. But now you know, you're going to have to help, arent you?" Frisk teases, moving off of Asriel and getting between his legs, pushing them open. "You did say you would, after all." 

Suddenly feeling like he was losing control of his situation, Asriel found himself only nodding weakly, his cock twitching as heat rushes to his face. "When did you get so dominant?" 

"Hm? Oh, Asri, this isn't me being dominant. I'm just making sure you aren't going to change your mind on me last minute." Frisk smiles, brushing a few strands of hair away from their face and reaching beneath the water to their elder sibling's crotch, gently wrapping their slender hand around Asriel's quickly-hardening manhood. 

Asriel bleats quietly in embarrassment, entirely convinced the red on his cheeks would become a stain on his skin if this kept up. "This isn't you being dominant, Frisk? I'm not sure I should ask what you're like when you are being dominant." 

Frisk's smile widens as they gently stroke Asriel's cock to it's full hardness. "Dearest brother, you don't need to act so shyly. After all, if you want me to top you, I wouldn't mind being dominant too." 

Asriel covers his face with his hands, whining quietly from a rapidly deepening amount of embarrassment. "I really hate how hot you sound when you talk like this, Frisk." 

Frisk laughs softly, climbing up against Asriel again to whisper in his ear. "So you do like being the submissive one from time to time, hm?" 

Satisfied by the silent, but clear answer Asriel gives by squirming underneath them, his erection twitching in their hand, Frisk gently sinks their teeth into Asriel's ear, moving their hand from Asriel's cock and instead pressing their fingers against his entrance instead. 

Feeling Frisk's slim fingers against a previously untouched part of him makes it impossible for Asriel to contain a loud, whimpering bleat as he bucks his hips up against Frisk, unintentionally grinding against them. "F-fuck, Frisk. Stop screwing with me, and get on with it." 

"You're desperate all of a sudden, aren't you Asri? Have the changes I've undergone also brought some about in you, I wonder?" Frisk laughs softly, placing gentle kisses along Asriel's collarbone and neck, their finger gently teasing against him before eventually sliding into him. 

Frisk can't help but relish how satisfied Asriel sounded as their finger, aided by the warm water from the bath, slid into his tight, virginal ass. "I'm gonna have a lot of fun taking you, you know. I've wanted this for a long time, Asri." 

Asriel shifts, squirming and moaning as his breathing becomes short and ragged. "I-is that so, Frisk? You could have t-told me, y'know. Fuck, g-goddamnit that feels weird. Your fingers are pretty small, arent they?" 

"Fingers, plural? No, Asri, this is just one. This-" Frisk punctuates their sentence by forcing a second finger into their lover's rear. "Is what two fingers feels like."   
Asriel groans loudly, his back arching as he squirms against Frisk, his whole body burning with the harsh fires of arousal. "F-Frisk, stop teasing me already, will you?" 

"Teasing? I'm just making you prepared, Asri." Frisk replies softly, working their fingers into Asriel as they continue peppering his neck and collarbone with kisses. "I don't want this to hurt after all. I want you to enjoy it." 

"Y-you won't have to worry about that. I'm just impatient, Frisk." Asriel admits, unsure where to put his hands as he squirms beneath Frisk's ministrations, feeling his arousal building with each passing moment. "I can't...last during foreplay as easily as you can." 

Frisk smiles against Asriel's tense neck, parting their fingers inside him and feeling him writhing beneath them bringing them far more pleasure than they expected. "I know. But this is necessary, and you can suck it up and deal with it, can't you." 

Asriel groans, both out of intense pleasure and equally intense frustration that Frisk wouldn't get on with what he knew both of them wanted now. The elder sibling couldn’t help but feel a little concerned at how easily he had slipped into submissiveness, considering he was supposed to be the more dominant one in the relationship, but felt even more concerned at how much he was enjoying having Frisk take charge like this. 

"I promise, all of this will make the real thing so much more enjoyable." Frisk reassures their partner, still slowly and carefully fingering Asriel while making sure to stretch him somewhat so he would be more capable of taking them. 

Neither of them spoke for a while after that, the room silent other than the pair's quiet breathing and the soft swirling sounds of the water being shifted around by Frisk's movements. After a while, however, Frisk broke the silence, uttering a sentence that Asriel was more than happy to hear.   
"I think that should be enough." 

"Oh thank god." Asriel sighed, still tense and twitchy beneath his partner. "Can we please get to the good part now?" 

Frisk pouts slightly, gently pulling their fingers from Asriel's tight, twitching ass. "You don't like being fingered, Asri?" 

"It's not that. I just...really want more, Frisk." Asriel speaks quietly, intensely embarrassed. "I want you inside me. Properly, not just fingers." 

Frisk smiles, moving so that they're properly positioned between Asriel's legs, slowly grinding up against him. "Say it properly, Asriel. Don't half-ass it now, tell me what you want me to do to you." 

"Do I have to?" Asriel asks nervously, unaware that this was how far Frisk wanted to take control. Normally, even when he was acting particularly dominant, he wouldn't ask Frisk to speak in specific ways. 

"Yes, Asri, you do. I want to hear what you want me to do to you." Frisk smiles, bearing their slightly sharpened teeth to Asriel as they grind up against him harder, still refusing to go any further. 

Asriel squirms uncomfortably, pausing for a moment before caving and nodding weakly, finding his voice particularly weak all of a sudden. "F-fine. Fine, Frisk, if that's how you're going to play it. I...I want you to fuck me. Please." 

"See, that wasn't too hard, was it?" Frisk replies with a soft smile, repositioning themselves before gently thrusting forward, pressing up against Asriel and sliding into him, exhaling softly as they feel his ass stretching around them, accepting them surprisingly well. "Unlike you. You're more than a little hard." 

"Ugh, shut up." Asriel groans, tensed up from feeling Frisk inside him, a sensation entirely unlike anything he had ever experienced before. Small rivulets of steam started rising from the bathwater as the caprine's magic sparked a little from his hands, immediately extinguished by the water around him. 

Frisk laughs softly, taking care to push forward slowly, gripping the bath either side of Asriel's head as they do so. "Sorry, I had to. How is it, Asri? I'm not moving too fast?" 

"No, it's fine. M-more than fine, this feels amazing." Asriel admits breathlessly, shifting his weight and pushing up against Frisk slightly. "E-even though I don't think you were this big before." 

Frisk pauses, blushing intensely. "W-what? Where did that come from?" 

"I'm serious. You feel thicker, and just...bigger than you used to." Asriel admits, feeling a little glad that he had been able to break Frisk's dominant facade. "Maybe that's another change you went through, but didn't notice?" 

Frisk shrugs weakly, a shiver of embarrassment running down their spine. "M-maybe." Determined not to let Asriel's sudden compliment get to them, Frisk continues what they were doing, gently and deeply pushing into their elder brother. "I'm glad you're enjoying this though." 

"O-of course I am." Asriel grunts, breathing heavily through grit teeth as he bucks his hips weakly, feeling his erection twitching and leaking a few beads of precum into the hot, still steaming water. "You seem to be, too." 

Frisk laughs quietly, finally hilting into Asriel and feeling his fur pushed up against their crotch. "What gave it away, Asri? I'm curious." 

Asriel blushes, laughing hoarsely. "Yeah, okay that was stupid of me to say." 

"No kidding." Frisk teases, leaning down and kissing Asriel softly, overcome with Asriel's scent as the kiss rapidly deepens, the two switching control as their tongues glide between each other's mouths, Frisk slowly and rhythmically starting to move their hips against Asriel, shallow and rapid thrusts bringing them together over and over again. 

Asriel groaned into the kiss, falling away from it and drooling slightly, his long tongue falling free of his mouth as he twitches and squirms underneath Frisk, the feeling of their now-furry lower half against him new, but not something he was about to complain about. "S-shit, Frisk." 

Frisk smiles, leaning against Asriel as they keep thrusting, the water shifting and agitating around them as they do so. "God, Asri, you're really tight. I might not last long like this." 

Asriel blushes, looking to Frisk as he writhes beneath his lover, his cock twitching and leaking more fluids into the water, enough that it's becoming visible on the surface of the bathwater. "Please, Frisk, don't stop just yet. Keep fucking me, p-please." 

Frisk can't help but feel a small rush of joy at hearing Asriel act so submissively, begging for them to fuck him in much the same way they had begged him in the past. "I'm not going to stop until I've pushed every last drop of my seed into you, Asriel." 

The caprine bleats in embarrassment, a rush of dirty thoughts suddenly running through his mind as he looks away from Frisk, unable to stop himself from pushing his hips up against his smaller lover. 

Frisk laughs softly, leaning down and sinking their teeth into Asriel's neck as they speed up their thrusts, fucking their older brother deeply and more roughly with each passing moment. Feeling their older brother squirming and tensing beneath them only drives Frisk on, moving one of their hands beneath the water to stroke   
Asriel's aching, dripping erection. 

Barely a moment later, Frisk feels Asriel's semen coating their hand, sticking to their fingers and clinging to their skin. Frisk moves up, continuing their thrusting as they pull their hand out of the water, making a show of licking Asriel's cum off of their hand. 

Asriel whimpers quietly, feeling spent and unable to look away from Frisk's deliberate show, his arousal burning deep inside him as he watches Frisk cleaning his thick, gray seed off of their slender fingers. "F-fuck, Frisk, you're so hot. You know that?" 

Frisk smiles, licking their lips teasingly as they swallow down their lover's fluids, moving their hands to Asriel's hips and fucking him more aggressively, their own arousal quickly becoming unbearable as they pant and groan, cursing under their breath. "F-fuck, Asri, I think I'm...I think I'm gonna cum." 

Asriel smiles softly, his chest heaving. "D-do it. I want you to cum in me, Frisk. Let me feel what you feel." 

Frisk grunts quietly, a little concerned that their motions would cause water to spill from the bath, but finding it hard to care as they thrust harder and faster, only lasting a few more, short moments before they thrust as deeply as they can, hilting into Asriel's ass as their orgasm tears through them, their breathing hoarse and ragged as their seed pools into their lover. 

"It's...sticky. Like, really sticky." Asriel remarks, shifting a little and sitting up slightly as Frisk pulls free of him. "And there's quite a lot, too. Your virility must have been changed as well, I guess." 

Frisk blushes, crawling beside Asriel and suddenly feeling the more intense weight bearing on their legs from their new fur. "Maybe it did. That...I did alright, didn't I? I mean, I've never done that before." 

Asriel smiles, wrapping his arm over Frisk's shoulder and holding them close, not very surprised at how quickly Frisk dropped the dominant persona they had mere moments ago. "You did great. It felt amazing, if I'm gonna be honest. I didn't expect it to feel so good, but, yknow. It did." 

Frisk smiles softly, leaning against Asriel's shoulder as their breathing starts to calm to a more regular level. "That's good. I was worried I was moving too fast, or too roughly, or whatever." 

"No. It was good. I had fun." Asriel reassures Frisk, gently coiling their hair around his fingers. "Maybe we can switch it up from time to time. I'm not sure if I prefer being a bottom or a top yet, but...I'm willing to be both for you, Frisk." 

"That sounds good to me. Although, now we should get clean. We don't know when Mom will be back after all, and now that we, and the bath are a mess..." Frisk trails off, well aware of what Toriel's wrath could entail, making them all the more fearful. 

"Yeah, that's a good plan."


	14. Learning the smaller things.

**Notes for the Chapter:**

> Hey everyone, Aithe here. I'm not too sure on how this chapter feels, if I'm honest. I'm not sure if it flows all that well, or if it's choppier than the others; so I'd really appreciate some feedback on that. Either way, I hope you all enjoy.

"Maybe we should plan ahead a little better next time." Frisk admits sheepishly, looking toward their rather annoyed elder sibling. 

"Oh, you think? It took me half an hour to clean you out my fur, Frisk. Half an hour!" Asriel whines, rubbing himself down with a towel. "Why didn't you tell me it was a nightmare to clean up after sex?" 

"I didn't have fur until yesterday, Asri. I couldn't have known that it would take so long. It normally only takes me ten minutes, fifteen at most, to get clean after you're done with me." Frisk shrugs, more than satisfied to let themselves drip dry after already having towelled down. 

"Well, I guess we know now." Asriel replies half-heartedly, feeling as exhausted as he always did after bathing. Even with his fur mostly dry by now, his whole body felt heavy. "I'm not sure if this will make anything change in you, though. It might not be the sex, but more that you're the submitting one?" 

"Maybe. I mean, I was still submissive on the phone, so you might be right. I guess we'll just have to find out, though." Frisk speaks softly, worried that Toriel might come home and hear them. For now, at least, they were still alone at home but it never paid to be careless, in Frisk's opinion. 

"You seem to have settled into your new changes pretty quickly, though. You're stood up straight again, for instance." Asriel smiles, watching Frisk's back as they walk past him to dress. "And you can walk without me having to help you." 

"I hadn't really noticed. I guess my body is just, really receptive to these changes? I mean, some humans are more attuned to magic than others, right? And each of these changes is making me more magical." Frisk bends down to open the drawer beneath the closet, pulling out a pair of pajama pants. "Crap, will my clothes even fit me anymore?" 

"Well, your shoes certainly won't, now that you have paws. You can just borrow some of my stuff until we replace yours, it's not a problem." Asriel offers, kneeling   
beside Frisk to get some pajamas for himself. "That might be where Mom went, come to think of it." 

"Maybe. I feel a lot heavier now, though. I guess there's more mass to my new legs than my human ones. All this fur, and there has to be more muscle than there used to be. It feels kinda like I'm walking around with weights strapped to me, I guess?" Frisk questions with a sigh, picking out a pair of Asriel's larger pajamas and standing, stepping into them and breathing a sigh of relief when they found the fabric falling around them without slipping or feeling too tight. 

"That would make sense. Your fur is a little thicker than mine, or Mom's, too. Although I guess that's because we keep it shaved." Asriel shrugs, grabbing himself a pair of pajama pants and putting them on. "How are you liking them, though? It isn't too weird to walk around on new feet? Or paws, I guess." 

"It's about as weird as I can expect it to be. It's not unpleasant, but I'm not really used to it yet, either." Frisk replies, looking up to Asriel as they sit down upon their shared bed. "They're larger than my feet were, and they have pads which human feet don't. But, give me time and I'm sure I'll deal with them." 

Asriel nods, leaning against the closet doors. "I'm sure you will, you're nothing if not adaptable. I'm honestly kinda surprised you didn't get any taller. Your legs just changed, they didn't lengthen. So you're still gonna be shorter than me." 

Frisk groans, crossing their arms over their chest. "Don’t remind me. I hate being so short compared to you guys. I'm barely taller than Dad, and Dad's tiny!" 

Asriel smiles, shrugging slightly. "You're, what, five foot seven? That isn't too bad for a human, right? You aren't gonna be as tall as me, Frisk. And there's no way you'll end up as tall as Mom, or Asgore. It just isn't built into you." 

"I guess." Frisk replies dejectedly. "I just don't like being short. You're six foot five for crying out loud, and you aren't even done growing yet. I almost look like I could be your kid instead of your sibling." 

"Well, I guess? I mean, people keep mistaking me for Mom's husband. Considering Mom and Asgore decided that Asgore would be known as the King up here, and we'd be left out of it, nobody really knows any better." Asriel joins Frisk on the bed, lying back and stretching to ease some of the leftover tension in his muscles. 

"Well, some of the monsters know. They just choose not to bring it up." Frisk corrects, before dropping back and lying beside Asriel, staring up at the ceiling. "Don't you miss being Prince? All that money, and power?" 

Asriel shrugs. "I was young, so I didn't really care. And it's not like I have anything I need that much money for. All that being Prince would do is cause trouble for us, really. Now that you aren't having to be so active as our ambassador, Asgore can take care of most of the interspecies political stuff." 

"I guess so. But what about when Asgore gets too old to rule? He is still aging, right, even if Mom isn't aging quite as quickly? I don’t know how it works." Frisk trails off weakly, looking over to Asriel. 

"Boss Monsters like Mom and Asgore start aging again once their child stops aging, which is on my eighteenth birthday. Then, until I have a kid and they reach eighteen, I won't age another day. I think there's more to it than that, but that's all I know." Asriel speaks quietly because of his proximity to Frisk. "So, who knows? Eventually, Asgore will get too old to rule and then I guess someone else will have to take over. It might be me, it might be someone else." 

"So it's just a matter of waiting to find out, huh? I was never very good at that." Frisk sighs, closing their eyes and stretching, arching their back a little as they do so. "But I guess there's no way to change things. Wait, but if I'm turning into a monster, will I age? Or am I gonna turn into a Boss Monster like you?" 

"I'm not sure. My guess would be that you're turning into a Boss Monster. Maybe you'll stop aging too, until you have a kid. Most likely with me." Asriel replies, reaching up and taking Frisk's hand in his own, interweaving their fingers. "Although that won't be for quite a while. We aren't even adults yet." 

"You want to have kids one day?" Frisk questions, smiling softly as Asriel gently strokes their palm. "I never thought you'd want to be a father." 

"Some day, I think I would. When I'm older, or...well, yeah still older just not aged. Maybe I'd like a kid or two. I'm not sure." Asriel shrugs. "I think I'd be a good father. Maybe not quite as fatherly-looking as Asgore, but y'know. Maybe I should grow a beard or something." 

Frisk tilts their head a little, trying to visualise what Asriel would look like with facial hair. Or fur. They never knew which one it was. "What color would it even be? You're white all over, like Mom." 

"Oh, right. Duh. I guess that wouldn't work then. But hey, you could always grow one. It'd look nice on you, I think. White on brown, it'd be cute." Asriel teases, pulling Frisk closer to him. 

Frisk can't help but blush slightly, the warmth of Asriel's fur against them. They'd never really thought of growing facial hair. They could, they just normally preferred to keep it shaven. "You think so?" 

"Of course I think so. I love the way you look already, don't doubt that. But, y'know, maybe give it a try sometime." Asriel suggests, stroking Frisk's cheek and pushing some hair from their face, gently running his thumb over Frisk's slowly growing horns, which by now measured at least three inches long, by Asriel's best guess. 

Frisk's blush only deepens, a wave of embarrassment running through them. "Jeez, it's like we switched roles huh? I used to be the smooth, flirtatious one, but now that's you and I'm the nervous and embarrassed one." 

Asriel smiles slightly, fangs ever-so-slightly bared. "You bring out the best in me, what can I say? It's not like I'd lie to you, either, so you know every word that comes from my mouth is truth." 

"Ugh, can you not be so painfully smooth for just five minutes?" Frisk groans, burying their head against Asriel's fluffy chest. "You'd put old me to shame acting like this." 

Asriel laughs softly, the sound sending shivers down his younger sibling's spine. "I bet I would. But it's all directed to you, my darling Frisk. The one I love most in the entire world, above and beneath the surface." 

"Stooop!" Frisk whines, their cheeks burning hot from embarrassment. "Stupid furry jerk, stop making me so embarrassed!" 

"And why would I do that?" Asriel replies with a smile, coiling a few strands of Frisk's ice-white hair around his fingers. "After all, you only get more adorable the more embarrassed you are. The redder your cheeks become, the more I remember why I fell in love with you." 

"I hate you so fucking much right now." Frisk groans, gripping tightly to the fur on Asriel's chest. "You're such an asshole." 

"I love you too, dear." Asriel teases, tangling his fingers deeper into Frisk's hair. "Every single thing about you, from your horns down to your paws. You're my favorite person in the entire world, Frisk, and I'm gonna remind you of that every single day. Or at least until you get so annoyed that you hit me." 

Unable to even form a coherent response, Frisk only sighs, releasing Asriel's fur and looking up to him, their heart racing slightly at the sight of him looking down to them. 

"I mean it, Frisk. I'm not just teasing you. I love you dearly, and will do everything I can to make you happy. I want to spend the rest of my life with you, after all." Asriel speaks softly, kissing Frisk's forehead softly. "Stop aging together, maybe have some kids in the future. Get married, even." 

Frisk swallows hard, their heart feeling as if it must have skipped a beat with how badly their chest stung now. "Y-you want all of that? Seriously?" 

"Of course. I love you more than anyone else, Frisk. I wasn't really kidding when I was saying I'd need to save for a wedding ring. You're the one I want to be with for the rest of my days, however many of them are left." Asriel smiles, tightening his grip on Frisk. 

Frisk couldn't bring themselves to keep looking at Asriel, their lungs aching as their heart began racing faster than they could ever remember. They had known that Asriel wanted this relationship to be serious, and so did they. But they had no idea that Asriel might want to get married, or anything like that. It had never even crossed their mind. 

"Frisk? Did...did I say too much?" Asriel asks nervously, pulling away from the smaller sibling to keep from making them more uncomfortable than they currently looked. "I'm sorry if I did." 

"No, no it's not that. I just...I didn’t know you wanted so much from me, Asriel. I thought that, yknow, maybe this would last a few more months, maybe a year or two at most, and then we'd separate and find other people, other monsters perhaps. I wasn't really ready for you to come out and say that you wanted this to be forever." Frisk's response is rushed, even to them. But it was all they could do to even stop the desperate flow of words. 

"I do want it to be forever. But, if you don't, that's fine. It's not like we've really been doing this long enough to decide the future. I'm just telling you what my aspirations for us are." Asriel admits sheepishly, gently placing a clawed finger beneath Frisk's chin to make them look at him. 

"R-right, of course. But still, it's a little nervewracking, you know? I mean, you're my first real partner, and you want to be with me forever. N-n-not that I don't want to!" Frisk panics, blood draining from their face as they start to feel a little lightheaded from stress. "I do, I-I promise. I just, i-it's a lot to take in and I didn't realise how badly you wanted all that, and now I don't know how badly I want anything anymore, a-and..." 

"Frisk, it's okay." Asriel speaks softly, gently stroking Frisk's cheek. "I'm sorry for causing you stress. We can talk about it at a later date, alright? Perhaps when you aren't feeling quite so nervous about everything else because of my teasing you." 

Frisk nods weakly, their whole body wracked with uncontrollable, panic-induced shivering. "R-right, that would be best. I want to talk about it, f-find out what we want and stuff. I think. I don’t know, maybe. I'm so confused." 

"It's okay." Asriel reassures his smaller sibling, hugging them gently and running his fingers through their hair. "Just relax." 

Frisk whimpers quietly, focusing as hard as they can to regulate their breathing. "Doing my best. T-thanks, Asri, you're the best." 

"So are you, pumpkin." Asriel speaks calmly, simply holding Frisk against them while they calmed down. "I really am sorry for worrying you so much." 

Frisk shrugs weakly, their breathing slowing to a more regular pace. "It happens. I'm easy to worry, so y'know." 

"That's not the point, Frisk. I don't want to make you worried like that, it isn't good for your heart." Asriel scolds Frisk softly, moving so he was looking at Frisk directly. "I don't want you getting ill. We can't afford that, with how you're changing right now." 

"I know, I know. It's just hard not to get worried, yknow? Everything gets to me. What people say, how they look at me, or you if I'm with you. I'm just easily rattled, that's all. I can live with it." Frisk looks away nervously, unable to bring themselves to look at Asriel. 

"What do you mean, what people say, or how they look at you? What kind of things do they say?" Asriel questions, now even more concerned than before.   
Frisk freezes, silently cursing themselves for being so careless. "Nothing, it was just an example. It's nothing, alright?" 

"Frisk, if people are-" 

"They aren't. Nobody says anything. I'm sorry, I shouldn't have brought it up." Frisk feels the too-familiar rise of panic in their chest, doing everything they can to stop themselves from showing just how nervous they now were. 

"You're not convincing me, Frisk." Asriel gently holds Frisk's chin, forcing them to look at him. "Tell me what's going on. What kind of things have people said?"   
Frisk swallows hard, feeling themselves starting to shake from fear. "Nothing. Please, drop it. Please." 

"Not if it's gotten you this panicked. Please, Frisk, I need to know what's going on." Asriel's voice is soft, but offered no chance of resistance. "I can't help if you don't tell me." 

Frisk whimpers quietly, their heart sinking. "It's not a big deal, okay? It doesn't even happen anymore, so don't worry. It's nothing, Asriel." 

Asriel sighs quietly, pulling himself away from Frisk and sitting up upon the edge of the bed. "Alright, I get it. I'm sorry for being pushy." The caprine sighs to himself, wringing his hands in his lap. "Sorry, Frisk. I just...I can't bear the thought of people hurting you. It makes me so angry." 

Frisk sits up themselves, pulling their knees up to their chest. "I know. I didn't want to upset you, Asriel. Please don't be mad at me." 

"I'm not mad, Frisk. I'm just worried. I don't want you to get hurt. You never told me a lot about your past but it's obvious that it wasn't good. I don’t want you to hurt   
like that again. I want to do everything I can to keep you safe." Asriel claws at his arms, worried that the telltale markings might make their way to his fur any   
moment. 

Frisk crawls over to Asriel, sitting behind him and wrapping their slender arms around his shoulders. "It's okay, Asri. I understand, and I appreciate it. But you can't worry this much, it isn't good for you either." 

Asriel scoffs quietly, hanging his head. "Yeah, I know. But like you said, it's not easy. I guess we're both caught in our own situations huh?" 

Frisk smiles, nuzzling against Asriel's cheek. "I guess so, Asri. Thank you, though, for caring. It really means a lot to me, y'know." 

Asriel reaches up, ruffling Frisk's hair. "Yeah? I'm glad, then. Let's try not to worry each other too much now though, yeah? I don't want any more stress than I already have, and I doubt you do either." 

"No kidding." Frisk laughs softly, hugging Asriel tightly. "I love you, Asri. But don't ever call me pumpkin again." 

"Duly noted." Asriel retorts, feeling calmer with Frisk's weight against him. "I'll have to figure out another petname for you, but I can do that." 

"No, I would really rather you didn't." Frisk replies, shivering a little. "I don't like petnames. They sound weird, especially when I already have a name." 

Asriel shrugs. "Alright, if that's what you'd prefer. But, what should we do until Mom gets back?" 

"Hmm." Frisk hums to themselves as they think. "We could always make out? It's been a pretty long time since we did that without there being sex involved." 

"That sounds good. A good way to de-stress too." Asriel quips, before he pulls Frisk's arms away from his shoulders, standing in front of them. "How, though? You wanna be sat on my lap, or led beneath me, or..." 

"Led beneath you sounds good. I like being beneath you, sexually or otherwise. It makes me feel safe." Frisk admits softly, feeling a little embarrassed. "So that'd be nice, if we can." 

Asriel nods, stepping up and placing his hand on Frisk's chest, pushing them back and climbing over them, looking deep into Frisk's eyes. "Y'know, I don't think I ever told you how much I love your eyes. They might be my favorite part of you." 

Frisk feels themselves blushing, struggling not to look away. "My eyes, really? I always thought they were ugly. There's so little color to them, it almost looks like I'm blind." 

"They look beautiful, Frisk. I could get lost in them forever, if I was so inclined." Asriel teases, leaning down and gently kissing Frisk's forehead, before moving his weight and kissing his lover straight-on. 

Frisk melted into the kiss immediately, reaching around Asriel's shoulders as if to keep him in place. There was something about having Asriel atop them like this that made his body heat feel so much more intimate to Frisk, although they couldn't figure out why. 

Asriel smiled against Frisk, tangling his hand into their hair as he pulls back for a brief moment before delving back in, biting at Frisk's lower lip and drawing his tongue against theirs once their mouth opens shortly after. 

Frisk had never told Asriel that their favorite part of him was his tongue. It would always have been a weird thing to say. But every time that they kissed, it was quickly reinforced as fact. The sheer size of it was enticing in a more carnal manner, but it was the dexterity that he seemed to possess with it that Frisk enjoyed so much when they were close like this. 

It wasn't as if Frisk had anyone to compare Asriel to when it came to kissing, but the younger sibling couldn't imagine it would be anywhere near as pleasant to kiss anyone else. Although Frisk wasn't entirely convinced that they weren't biased, all things considered. 

Asriel held himself against Frisk for a few moments longer before pulling away, his chest heaving slightly with his deep breaths. "I love you, Frisk. I don't say it often enough, but I really do love you." 

Frisk blushes slightly, their eyes constantly flicking between Asriel's own, and the thin strings of drool that clung to his fur and mouth. Trying desperately to subdue any unwanted, sexual thoughts, they struggle to find a suitable reply. "You, uh, don't have to tell me, y'know. I know you love me." 

Asriel smiles softly, kissing across Frisk's chin and down across the curve of their neck. "I know that you know, but I like telling you. And I like showing you. I just enjoy loving you." 

Frisk whines softly, their back arching beneath Asriel as they crane their neck to expose more of the dark flesh to him. "I th-thought I told you to stop being so smooth." 

"Hmm, you did. But I also told you it's more fun this way." Asriel pauses, well aware that Frisk was shivering from the heat of his breath against their neck, before baring his fangs and gently biting down, not hard enough to break the skin, but definitely enough to bruise. "Isn't it?" 

"Ugh, I hate you." Frisk whimpers, squirming and writhing beneath their monstrous lover. "I thought this wasn't meant to be a sex thing." 

"It's not. I just like marking you. Proving to everyone who looks at you that you belong to me. That you're my lover, and that nobody can ever take you from me." Asriel muses, kissing the newly-sensitive spot on Frisk's neck. "I love seeing the bruises and the bitemarks." 

"Of course you do, you pervert." Frisk's voice is soft, and breathy as they struggle to keep themselves from getting too aroused, as they already felt the burning deep within them the moment that Asriel's fangs touched their neck. 

"I won't deny I'm a pervert, but this isn't sexual." Asriel retorts, moving away to look at Frisk proper. "I just like the way it looks, as well as what it implies." 

"Don't you realise how embarrassing it is to have to walk around with them on my neck? I get stared at constantly." Frisk whines, finally voicing a concern they've had for a while but had always been too nervous to bring up. 

"Good." Asriel replies, smirking slightly. "I want them to stare. Although, if you'd rather I also left bitemarks on places that are less visible to the public, you should just ask me." 

Frisk swallows hard, a deep crimson blush forming on their cheeks. "Less public? What kind of places are you trying to imply?" 

Asriel winks, smiling down to his partner. "Well, let me see. The most obvious would be your thighs, wouldn’t it? Perhaps, the next time I go down on you, I can be sure to give your thighs the treatment they truly deserve. After all, you have such amazing thighs..." 

"No! N-no, don’t be ridiculous!" Frisk interrupts Asriel, their blush only worsening as they hear their voice cracking from embarrassment. "Y-you wouldn't even be able too, there's too much f-fur, and..." 

"Hmm, well I suppose that does make sense." Asriel replies, thoroughly enjoying seeing Frisk squirm. "I'm sure I'll figure something out, though, don't you worry." 

Frisk hates themselves for feeling a distinct tightening of fabric as Asriel winks at them, moving down to get at their neck again. "Damnit, Asri, can you stop being so hot for like, two seconds? Seriously?" 

Asriel laughs softly, nuzzling against Frisk's neck. "I'll take that to mean you want to stop. I'll admit that's a shame, because I don't really want to stop until every inch of your neck is bruised or bleeding, but I'll stop." 

Frisk breathes a deep sigh of relief as Asriel moves away, dropping down to lie beside them. "Thanks, Asri. It's fun, doing that, but I don't want to get too turned on." 

"Huh?" Asriel looks down, genuinely surprised that Frisk had become aroused, having thought they were just playing along. "Oh. Oops." 

"Oops? Really?" Frisk groans, rolling onto their side. "That's all you have to say?" 

"I didn't mean to get you hard, Frisk. I'll be more careful in the future." Asriel replies, scratching the back of his head. "I didn't realise you were so sensitive." 

"Are you kidding? I'm crazy sensitive. It took all my willpower to only get this aroused." Frisk laughs nervously, goosebumps forming on their skin. "It's a mixed blessing, for sure." 

"Sounds like it. But now that I know, I'll be more careful alright? I don't want to make you more embarrassed than I'm planning." Asriel smiles softly, pushing some hair free of Frisk's face, a passing thought that he really should buy them some hairbands to hold their hair back. 

"I'd appreciate it." Frisk returns the smile, shifting up against Asriel and hugging him closely. "Do you wanna take a nap maybe? You looked kinda tired after the bath, and I'm exhausted from all this stress." 

Asriel laughs softly, before rolling Frisk over and moving behind them, spooning them. "Sure, if we lie like this. Less chance of me being smacked or something." 

Frisk smiles warmly, feeling Asriel's warmth against them helping calm their nerves as they feel their arousal fade. "Got it. Love you." 

"Love you too. See you when you wake up."


	15. Introspection

**Notes for the Chapter:**

> Hey everyone, Aithe here. I'm using this chapter to try and flesh out the situation a little more, but I'm not overly confident with how it's written. But anyway, as always, feedback is greatly appreciated and I hope you enjoy.

Toriel didn't know, if she was honest, how she truly felt about what was happening between her children. It wasn't that she disapproved, exactly; she was glad that they had both found someone that made them as happy as Sans made her. 

But it was the fact that it was changing Frisk so completely, and so rapidly, that the elder goatmonster was struggling with; a feeling only made stronger when she saw Frisk in Asriel's arms. 

The pair were asleep, as she often found them, but Frisk looked so different to how they had only a fortnight before. They were no taller, but they certainly seemed broader, and so much of their body was no longer human that Toriel sometimes found it hard to believe it was still the same person. 

Sighing softly to herself, Toriel closed the door to her children's bedroom, making her way to her own. The house felt so empty with them asleep, and her husband away for work purposes, as he often was. 

Allowing herself to relax for the first time in longer than she cared to admit, Toriel sagged, almost deflating as she walks over to her bed, sitting upon the large mattress. So many things had happened over the course of two weeks that she hadn't had the chance to catch up with it all. It was only now, in a brief moment of peace, that the reality of just how much change she had to accept. 

Her children, while happy, were now in a relationship that was, to her knowledge, entirely illegal amongst humans and barely acceptable amongst monsterkind. While monsters didn't have laws against it like humans did, it was still widely frowned upon and those engaged in such things were often hounded and harassed for their actions. 

And if that wasn't complicated enough for her to try and comprehend, that exact relationship was causing her younger child to become incredibly physically different, to the point that they were literally changing species. Toriel didn't mind this, of course, her first thoughts were always to what would make them most happy, but it was more than a little disconcerting to see such changes happening, especially so quickly. 

What worried Toriel most, however, was that she found herself becoming less and less accepting of what was happening as it continued. She found it harder to live with the fact that her children would allow themselves to love each other in a way so unlike how she believed they should; especially when such a love was taking her youngest child away from her. 

She knew that such thoughts were unfair, and more than a little unkind. They could even be considered cruel, but she couldn't stop herself from thinking them. Frisk wasn't what they used to be, and never would be again. And that was due to Asriel. 

It always came back to Asriel, somehow. Every change, every new thing about her family, it was always because of him; and Toriel hated that. She tried as hard as she could to be accepting, but it was becoming far too much of a strain to do so. 

She hated herself for thinking in such ways, for such hateful and cruel thoughts about her own son of all people, but it was one of the few things she could trust anymore. Her life was changing far too quickly in too many ways, so as far as she was concerned she had to cling to whatever she could that was constant, and normal. 

And blaming Asriel had become normal, now. It made Toriel feel sick to her stomach, but that was what had become of her – that she had become so used to blaming Asriel for all that was happening that it had become normal. She never said it directly to him, but that didn't mean she didn't harbor this kind of thoughts. 

The elder caprine sighed deeply, resting her head in her hands. She hated times like this, when she realised just how much she lied and how many things she hid. All the falsehoods that held her character together splintered at times like these and she didn't know how to deal with it. 

It wasn't as though she wasn't trying. She did everything she could to be a good mother, a good role model. But, as Asriel himself had often pointed out, she was too pushy and too prone to playing favorites. She had always favored Frisk, no matter how much she didn't want to admit it. 

Perhaps it was because they reminded her of Chara, and when she had been happy with Asgore and Asriel, as a family. In truth, Toriel didn't know her own reasoning. But Frisk always made her happier than Asriel did, despite Asriel being the lower-maintenance, easier to deal with child; at least until recently. 

Clawing at her hands, Toriel did what she could to fight back showing any emotion, in case either of her children were to walk in. These thoughts were unhealthy, and she knew that. But she knew that she couldn't hold them in forever, for if she tired then things would end up going terribly wrong in some form; and she couldn't allow that. 

"What have I become, thinking so ill of my own family? My own son?" Toriel speaks softly, her voice cracking from heartbreak. "I suppose I fit the more traditional definition of a monster now, don't I?" 

Sighing deeply and wringing her now-sore hands, Toriel stands and brushes herself down, walking from her bedroom and down the stairs, needing something to occupy herself before her thoughts get the better of her. 

Seeing a pile of papers that still need to be marked, Toriel finds herself, for the first time, glad to have something monotonous to do. 

\-------------------------------------------------- 

The first thing Asriel feels when he wakes is warmth against his chest. Looking down, the young goatmonster smiles softly, a still-sleeping Frisk curled up against him, their back pressed up against him. 

Unable to resist, Asriel brings his free hand up to Frisk's hair, gently trailing his clawed fingers through it, and marvelling at how the once-brown fibres were now as white as he himself was. So many things about his younger sibling had changed, and Asriel realised that he was falling deeper in love with them as they underwent each change. 

That in itself worried him slightly, knowing full well that the changes weren't purely aesthetic. Frisk's very existance was being changed with each visible change, their SOUL slowly turning as white as their hair. 

Did that mean that Asriel was more willing to love a monstrous Frisk than a human one? He didn't know. Frisk was still Frisk, regardless of whether they had skin or fur; but Asriel couldn't deny that he felt more content in their relationship as the changes started happening. 

He knew part of that was because Frisk themselves had seemed happier recently. As painful and difficult as each change was for them, each one seemed to make them more cheerful once the pain had passed. And there were few things that would raise Asriel's mood faster than seeing Frisk feeling genuinely happy, especially since they had had so many problems in the first few days of their relationship. 

Coiling a few strands of his lover's hair around his fingers, Asriel sighs quietly. He knew so little of Frisk's life before they had fallen to the Underground, and he had met them in his...other form. And Frisk had always been so unwilling to share that Asriel had never pushed. He knew something must have happened, and something awful at that, for why else would they have tried to escape it? 

But that didn't mean he knew what that was, and why Frisk had tried to do something so severe as run from whatever life they once had. Nor was he willing to try and ask them. Seeing Frisk happy was too important to him to risk triggering some kind of relapse into their misery. 

Frisk themselves, now that he thought about it, was too important for him to let something like that happen again. The young caprine was entirely aware that he was possessive towards Frisk, but he loved them more dearly than perhaps even his own parents. There was something about Frisk that caused a blazing, crimson fire in his SOUL, a desire to protect far stronger than anything else he had ever, or likely would ever experience. 

Keeping that desire in check was difficult for Asriel, but he had done well with it, as far as he knew. There had been slip-ups and anger, and small fights, but Frisk always understood. No matter what happened, Frisk was willing to forgive, and move on; something that his parents never did. 

Letting Frisk's hair fall free of his grip, Asriel sat up and moved to the edge of the bed, running his hands through the thicker fur atop his head. Did this mean he loved Frisk more than Toriel, or Sans? Did he even care if that was the case? If he was honest, the young caprine already knew the answers to those questions, which sent a shiver of concern and even a little fear down his spine. 

"I guess even the happiest families have problems, huh?" Asriel speaks softly, so as not to wake Frisk. "Not that it matters. We're stuck here until it's possible for us to move out, huh Frisk?" 

Sighing deeply, Asriel hangs his head. "I wish I was able to take you somewhere, find our own place. Somewhere we can be happy, and not have to worry about dealing with Mom and Dad. But I just...can't afford that, not yet. Maybe in a few months, when my birthday comes around and I get the money Asgore promised for me. Maybe then, we can move out and live together." 

Looking over his shoulder to Frisk's sleeping form, Asriel smiles weakly. "Would you even like that? God, I really don't know. I hope you would, but maybe you'd think I'm pushing too hard, moving too fast. Is there even a 'too fast' anymore? We've done so much, and so many things have happened, and it's only been a couple of weeks." 

Shrugging weakly, the young caprine stands, trying not to shift the mattress too much and wake Frisk. "I guess we'll figure it out, won't we, someday. I'll talk to you about it, don’t worry." 

\------------------------------------------------------ 

Frisk can't help but feel cold when they wake, the warmth of their partner having gone missing at some point while they slept. Rolling onto their back, Frisk sighs and stretches out some of the tiredness from their muscles. 

Expecting that Asriel had most likely gone downstairs, given that they couldn't hear any water running and it was unlikely that he'd go for yet another bath; Frisk decided to take some time to think. 

A lot of things had happened to them, after all, and they felt like it was as good a time as any to acknowledge and compartmentalise it all. They couldn't risk letting control slip from them, not again. 

So, sitting up with a solid goal in mind, Frisk climbs from their bed and walks over to the desk they share with Asriel, pulling out some lined paper and a fountain pen to write with. "Alright. Lists help, let's work with a list." 

Finding solace in the near-silence of their room, the quiet scratching of pen against paper being the only sound within, Frisk sighs contently once they find the list complete, line after line of the changes that they had undergone, written in great detail, now covering the paper. 

Content with their work, and with their mind now feeling clearer, Frisk stands from their chair, pushing it back beneath the desk. "Alright, good. That's better." 

Frisk speaks softly, sighing deeply. "I hadn't realised just how many little things that changed. The large changes swamp them so much, that the small things kept getting lost amongst them. I'll need to pay more attention." 

Tightening their grip upon the wooden-backed chair, Frisk lowers their head slightly, feeling the weight of their horns more than they normally would. "I shouldn't think too much. If I overthink, I'll end up getting stressed out. These changes arent bad, they're a help. They're helping me become a monster, like I want to be. Remember that, Frisk. You wanted this." 

An intense feeling of fatigue washes over Frisk as they fall silent again, the realisation that they had nobody else to blame but themselves for the torturous agonies that they had undergone being a particularly heavy one. "Nobody to blame but myself. The pain is all my fault, and nobody else has to bear it." 

Walking over toward the mirror in the room, Frisk inspects just how different they looked now. The thick brown fur that covered their lower half, the large paws that replaced their feet; the list went on. They knew so, they'd just written that exact list. They hated being half-formed like this, their natural impatience driving them to want to finish the job, even knowing they likely couldn't take another change for a while. 

"I can't complain. They've all done so much for me already, it wouldn't be fair to complain." Frisk scolds themselves, yanking at a few strands of their hair. A small punishment, but punishment enough. "Stupid child, daring to think for yourself." 

Sighing heavily, Frisk lowers their head, now stinging from their self-inflicted punishment. "I don't know why I couldn't just stay quiet. Instead of causing trouble, I should have just faked happiness." 

Shrugging weakly to themselves, Frisk walks out from the room, listening for any sound to find out if there was anyone else in the house.


	16. One final change

**Notes for the Chapter:**

> Hey everyone, Aithe here. I'm finally coming off of hiatus on this piece. My updates here will likely still be slow, as I'm between this and my other work, if you're familiar with that. Either way, I'm sorry this chapter is so short, and I really, really hope it's good enough.

It wasn't often that Frisk felt like they wanted to Load. They could, in fact, count the number of times it had happened since they came back to the surface on one hand. 

But right now, bent double and brought to the brink of tears from pain, they were desperate for it. If they had the strength of mind to do it, they were sure they'd do so. Pushing the world back before this pain, this overwhelming and blinding pain that feels like it's pulling apart every muscle that wasn't already transformed; it sounded like an unreachable ecstasy. 

"Frisk. Frisk, I'm here. How are you holding up?" Asriel's voice is half-desperate, half-hopeful as he sits beside Frisk, his grip warm against Frisk's freezing skin. 

It causes Frisk to startle, their breathing quick and labored as they look up to their elder sibling, their bloodshot eyes portraying the panic, and hopelessness they felt. It pulled at their heart as badly as the pain pulled at their body, and it was all they could do to hold back the tears that threatened to fall. 

"Shit, it's getting this bad? Here, lie down and I'll try to help. Is that okay?" 

Frisk nods, overtaken with pain as they drop down to their back, their shirt falling beside them. Looking down over themselves, Frisk finds some small comfort that this is likely to be the last time they would undergo such pain, with so little of them left to transform. It wasn't much comfort, but it was all they had and as such, they clung to it desperately. 

\------------------------- 

Asriel hates seeing Frisk like this. Knowing that they made it worse on themselves for reasons they wouldn't explain and that he couldn't understand. It wasn't as if he didn't try, he practically harassed Frisk to allow either himself or Toriel administer healing the moment Frisk looked like they hurt. 

As he climbed atop Frisk, kneeling across their waist with his focus entirely on his lover's wellbeing, Asriel felt the now familiar burn beneath his skin as he placed his hands as gently as he could onto Frisk's tensed, writhing muscles. It was as fascinating as it was terrifying to the caprine to feel Frisk's body rebuilding itself, the muscle fibres re-arranging and their skin bringing forth the deep brown fur that separated Frisk from the others in their family. 

Asriel closed his eyes as the healing magic flowed this his hands and into Frisk, a faint orange glow between the two surfaces as Asriel guided the powerful magical energies through Frisk's body, pinpointing as best he could where the pain was most severe. He didn't know how helpful this would be, but it was definitely better than letting them suffer. He had to do something, after all, and this was all he could do. 

He holds Frisk down as best he can as they buck beneath him, weak and desperate cries of pain escaping them. It breaks Asriel's heart to hear them so utterly defeated, but he trusts in them to make it through this. They have so many times before, and can't bring himself to believe that would change. 

Knowing full well the risks of forcing too much magic into Frisk's systems before it manifests naturally, Asriel withdraws his hands a few minutes later, his own breathing slightly labored from the strain of holding such an intense spell for such a period of time. 

"How are you feeling? Did that help at all?" 

His voice is quiet and breathy, tinged with just a little hope. He didn't know how he'd cope with the idea of failing them. Of failing Frisk again, and causing them nothing but more pain. 

"Better. Not good, at all. But I don't feel like my body is trying to collapse on itself." Frisk's reply is short, and as labored as Asriel's own speech, but it fills Frisk with hope, and a feeing they thought long gone, an intense rush of pure Determination. 

The shorter sibling sits up with Asriel still atop them, before wrapping their arms tightly around Asriel's midriff, listening to where his heartbeat would be, if he held organs within him. Frisk can't help but laugh softly, remembering how bizarre it had been when they had first been adopted, to find that they were the only member of their family that had a heartbeat. 

"We're going to get you through this, Frisk. You have to remember that, understand? No matter what, you'll make it through this. I promise." 

"I know, Asri. I believe you." 

Asriel wraps his arms as tightly as he dares around Frisk, returning their embrace as he lets out a breath he didn't realise he was holding in. He felt exhausted, overworked from the strain of having to use powerful magic as often as he had in the past few weeks, it had left him feeling more drained than he could ever remember being. 

"That's good to hear. At this rate, you should be completely changed within the next...two, three hours? The fur is all the way up to your neck now, after all. All that's left is your head, and then you'll be done." Asriel speaks softly, scared of how sensitive to sound Frisk might be with as much pain still in them as there was. 

"Yeah, this is pretty much the home stretch. I'm not looking forward to having my skull re-arrange, but I'm hoping it won't take long. That's the only mercy I can hope for now." Frisk replies with equally low volume, sighing sadly. 

They knew, and had known for a while, that the worst part would be the last. The changes that would happen to their head would be the most painful, if few in number. Their horns would grow to their full length, as would their tongue, and Frisk wasn't worried too much about those. But the thought of having heir facial structure completely changing, that was pretty scary in comparison. 

"It's going to be okay, Frisk. Only a few more hours, and then it's done. Okay?" 

Frisk's smile is bitter and weak as they decide against replying, already feeling too exhausted for what they knew would be happening over the remainder of the evening. 

\--------- 

It's only thanks to the aid of Toriel's healing magic that Frisk can even stay conscious. The pain is insurmountable, and if their tear ducts were functioning right now, they knew they'd be crying uncontrollably. As it was, they were forced to remain entirely silent, the searing heat of Asriel and Toriel's magic burning through every nerve in their body. 

There's nothing they can even compare it to. How could they, it wasn't as if this happened often. Nor was Frisk entirely sure the pain didn't make them regret the choice to begin at all. Most of the transformations, with a few blessed exceptions, had been incredibly painful but they had nothing on this one. 

Perhaps it wouldn't have been as bad if they couldn't hear it. If their ears didn't ring with the deafening sounds of their bones splintering under the pressure of the changes, every other noise muffled to near-silence as they writhe, their back arching despite Toriel's weight on their chest, the elder monster doing everything she could to dull the pain. 

Frisk found, and hated, that the worst part about this was that it worried others. If Asriel and Toriel didn't look so pained and worried about them, they wouldn't care. But the crushing guilt of forcing them through this because of something they wanted was absolutely ruinous for Frisk's already low self-worth. 

"We're almost done, Frisk. I promise you, there's so little left. Just a few more minutes and you'll be through it." Asriel's voice is strained, desperate and choked; but it holds some hope, or at least Frisk desperately hopes it's hope. They have so little they can believe in anymore. 

"Now, Frisk. I'm going to force the last facial change on you, as it can't happen without help. It's going to hurt, perhaps more than any other change, and I'm sorry for that but it must happen." Toriel's voice is stern, her concern masked as she gently opens Frisk's mouth, struggling not to wince as she pulls at Frisk's mouth, feeling the bones of her son's jaw splinter beneath her grip, held in place by the magical binding herself and Asriel has wrapped around Frisk's skeleton.   
It was all the elder caprine could do to swallow down her nausea as she watched Frisk fall unconscious, likely from the shock of such a severe pain; and continued pulling very slowly, forcing Frisk's facial structure to take a form much that of the others in the family. 

The shifting and twisting of Frisk's muscle fibres and bone structure as they aligned themselves with the magic their body was now capable of using, was a very unpleasant and almost sickening feeling, but Toriel knew it had to be done. This was the final step towards Frisk's new body, and things such as this would never need to be done again. 

"We're a-almost done, right Mom? Please say we're nearly there." Asriel almost pleads, nowhere near as capable of holding himself together as Toriel has been. The young goatmonster feels ready to burst, feeling as helpless as he had when he was fighting Frisk for the final time before they came to the surface. 

"We are, Asriel. But I am exhausted, and will need you to continue to heal Frisk while I rest. If I falter, they may fall irreparably ill. You must stay strong for them, Asriel. Do you understand?" Toriel's voice wavers, as she finally allows herself to rest, climbing from Frisk and allowing her son to take her place. 

"Perfectly. I won't let you down, Mom. You or Frisk. You can count on me." 

\------------------- 

Asriel finds himself counting. Counting the seconds, the minutes, the hours even. It feels like an eternity, and Frisk just will not wake up. They're still very much alive, their pulse attests to that. But it's been exactly nine hours, seventeen minutes and fifty-two seconds, and Frisk still hasn't opened their eyes or shown any sign of waking; and it is torturous. 

He had given up crying long ago, saving his strength to stay awake. Exhaustion had set in long before the tears had stopped, but he couldn't bear the idea of resting, not while Frisk could still wake at any moment. He had to be awake when they finally, finally woke from their seemingly endless sleep. It was the least he could do. He had to, at least, tell them of what happened, and comfort them if they needed it. 

More hours, so many more, passed. Asriel felt as if he would collapse any moment, but still could not allow himself sleep. The pain he felt, the exhaustion and fatigue, he despised how badly they affected him but he knew he needed to move on. He had to be strong for them, because he would fail them if he didn't. It was all he could think of anymore. 

It takes fourteen hours, thirty-six minutes and nineteen seconds for Frisk to wake. Asriel himself hadn't moved for most of that time; for he had expected his silent vigil to last far longer than it had. So deep was he in the trance-like state he had fallen into, that the young monster nearly left his seat with surprise at hearing Frisk stir. 

It was clear they were trying to speak, but Asriel got there first, a quiet warning to remain silent. He could hear his voice shaking, but he couldn't let them be in more pain than they undoubtedly already were. 

"You'll be okay. You've j-just woken up, so you're probably sore at the least. Do you need me to get you anything?"   
A simple, yes or no question. All Asriel could muster, and easy enough for Frisk to answer, hopefully. The weak, struggling shake of their head is enough answer, and 

Asriel has to restrain himself from embracing his younger partner, no matter how desperate for that he feels.   
"Alright. Just...god, I don't know. I-I don't know what I'm meant to say, or anything. Just...I hope you're okay, Frisk. I really do." 

Frisk smiles, weakly and with little conviction, before freezing up as they notice the effect the changes had on them. Their face felt heavier, as everything else did, but the new shaping felt incredibly alien to the young monster. Nervously, they bring a hand up to their new muzzle, finding far less concern with the fact that their hand was now much more paw-like than it had been; and gently touched the tender, newly-made flesh. 

Small spikes of pain lanced through them whenever they did so, but fascination made for an excellent way to block the pain, it turned out. So much so, in fact, although partially also because Frisk knew they were defiant to a fault, that the young, newly-turned monster decided they needed to speak. 

"A-Asri, is..." 

It was all they could manage. The words were weak, stuttering and with a voice that did not at all sound like Frisk's own. But it was a start. 

"I said not to talk, Frisk. You've been unconscious for over half a day, so you need time to recuperate." Asriel retorts, his tone gentle although painfully nervous. 

Frisk, reluctantly, nods and accepts that perhaps defiance might be the wrong path for once. Despite that, they arent able to resist forcing themselves into a seated position. Their muscles burn, feeling as if they're soaked in acid, but the satisfaction they get from something so simple as sat up is more than enough to dull the pain. 

Asriel reaches out, taking Frisk's hand in his own, interlocking their fingers as he takes in Frisk's new, complete form. The young human that he had fallen in love with, turned into a monster impressive enough to put most of their kind to shame. 

Their fur was thick, matted slightly from sweat, and would definitely need combing and likely cutting; but it was gorgeous nonetheless. Their horns had grown out to what would likely be their full length, with enough curve that it was unlikely they'd get caught on anything. Everything about Frisk's new body gave Asriel a rush of emotion. 

God, he was so in love. 

"You don't have to worry anymore. There's no more changes. You're fi-finally the monster you wanted to be, Frisk." Asriel hates that he finds himself choking on his words slightly, his grip on Frisk's hand getting all the tighter before giving in to his desires, nearly jumping from his chair as he embraces his younger sibling tightly. 

"I love you so much. I'm so happy to see you awake." 

"I l-love you, t-too, Asri."


End file.
